diff --git a/docs/conf.py b/docs/conf.py
index e53f785fe..dc7e6ece3 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -12,7 +12,7 @@
 class Mock(MagicMock):
     @classmethod
     def __getattr__(cls, name):
-            return Mock()
+        return Mock()
 
 MOCK_MODULES = ['pycurl', 'lxml', 'psycopg2']
 sys.modules.update((mod_name, Mock()) for mod_name in MOCK_MODULES)
diff --git a/pyspider/database/__init__.py b/pyspider/database/__init__.py
index 04755b904..a21638257 100644
--- a/pyspider/database/__init__.py
+++ b/pyspider/database/__init__.py
@@ -5,7 +5,9 @@
 #         http://binux.me
 # Created on 2014-10-08 15:04:08
 
-import os, requests, json
+import os
+import json
+import requests
 from six.moves.urllib.parse import urlparse, parse_qs
 
 
@@ -55,9 +57,8 @@ def _connect_database(url):  # NOQA
     scheme = parsed.scheme.split('+')
     if len(scheme) == 1:
         raise Exception('wrong scheme format: %s' % parsed.scheme)
-    else:
-        engine, dbtype = scheme[0], scheme[-1]
-        other_scheme = "+".join(scheme[1:-1])
+    engine, dbtype = scheme[0], scheme[-1]
+    other_scheme = "+".join(scheme[1:-1])
 
     if dbtype not in ('taskdb', 'projectdb', 'resultdb'):
         raise LookupError('unknown database type: %s, '
@@ -65,38 +66,29 @@ def _connect_database(url):  # NOQA
 
     if engine == 'mysql':
         return _connect_mysql(parsed,dbtype)
-
-    elif engine == 'sqlite':
+    if engine == 'sqlite':
         return _connect_sqlite(parsed,dbtype)
-    elif engine == 'mongodb':
+    if engine == 'mongodb':
         return _connect_mongodb(parsed,dbtype,url)
-
-    elif engine == 'sqlalchemy':
+    if engine == 'sqlalchemy':
         return _connect_sqlalchemy(parsed, dbtype, url, other_scheme)
-
-
-    elif engine == 'redis':
+    if engine == 'redis':
         if dbtype == 'taskdb':
             from .redis.taskdb import TaskDB
             return TaskDB(parsed.hostname, parsed.port,
                           int(parsed.path.strip('/') or 0))
-        else:
-            raise LookupError('not supported dbtype: %s', dbtype)
-    elif engine == 'local':
+        raise LookupError('not supported dbtype: %s', dbtype)
+    if engine == 'local':
         scripts = url.split('//', 1)[1].split(',')
         if dbtype == 'projectdb':
             from .local.projectdb import ProjectDB
             return ProjectDB(scripts)
-        else:
-            raise LookupError('not supported dbtype: %s', dbtype)
-    elif engine == 'elasticsearch' or engine == 'es':
+        raise LookupError('not supported dbtype: %s', dbtype)
+    if engine == 'elasticsearch' or engine == 'es':
         return _connect_elasticsearch(parsed, dbtype)
-
-    elif engine == 'couchdb':
+    if engine == 'couchdb':
         return _connect_couchdb(parsed, dbtype, url)
-
-    else:
-        raise Exception('unknown engine: %s' % engine)
+    raise Exception('unknown engine: %s' % engine)
 
 
 def _connect_mysql(parsed,dbtype):
@@ -115,14 +107,13 @@ def _connect_mysql(parsed,dbtype):
     if dbtype == 'taskdb':
         from .mysql.taskdb import TaskDB
         return TaskDB(**parames)
-    elif dbtype == 'projectdb':
+    if dbtype == 'projectdb':
         from .mysql.projectdb import ProjectDB
         return ProjectDB(**parames)
-    elif dbtype == 'resultdb':
+    if dbtype == 'resultdb':
         from .mysql.resultdb import ResultDB
         return ResultDB(**parames)
-    else:
-        raise LookupError
+    raise LookupError
 
 
 def _connect_sqlite(parsed,dbtype):
@@ -138,14 +129,13 @@ def _connect_sqlite(parsed,dbtype):
     if dbtype == 'taskdb':
         from .sqlite.taskdb import TaskDB
         return TaskDB(path)
-    elif dbtype == 'projectdb':
+    if dbtype == 'projectdb':
         from .sqlite.projectdb import ProjectDB
         return ProjectDB(path)
-    elif dbtype == 'resultdb':
+    if dbtype == 'resultdb':
         from .sqlite.resultdb import ResultDB
         return ResultDB(path)
-    else:
-        raise LookupError
+    raise LookupError
 
 
 def _connect_mongodb(parsed,dbtype,url):
@@ -157,14 +147,13 @@ def _connect_mongodb(parsed,dbtype,url):
     if dbtype == 'taskdb':
         from .mongodb.taskdb import TaskDB
         return TaskDB(url, **parames)
-    elif dbtype == 'projectdb':
+    if dbtype == 'projectdb':
         from .mongodb.projectdb import ProjectDB
         return ProjectDB(url, **parames)
-    elif dbtype == 'resultdb':
+    if dbtype == 'resultdb':
         from .mongodb.resultdb import ResultDB
         return ResultDB(url, **parames)
-    else:
-        raise LookupError
+    raise LookupError
 
 
 def _connect_sqlalchemy(parsed, dbtype,url, other_scheme):
@@ -174,14 +163,13 @@ def _connect_sqlalchemy(parsed, dbtype,url, other_scheme):
     if dbtype == 'taskdb':
         from .sqlalchemy.taskdb import TaskDB
         return TaskDB(url)
-    elif dbtype == 'projectdb':
+    if dbtype == 'projectdb':
         from .sqlalchemy.projectdb import ProjectDB
         return ProjectDB(url)
-    elif dbtype == 'resultdb':
+    if dbtype == 'resultdb':
         from .sqlalchemy.resultdb import ResultDB
         return ResultDB(url)
-    else:
-        raise LookupError
+    raise LookupError
 
 
 def _connect_elasticsearch(parsed, dbtype):
@@ -198,10 +186,10 @@ def _connect_elasticsearch(parsed, dbtype):
     if dbtype == 'projectdb':
         from .elasticsearch.projectdb import ProjectDB
         return ProjectDB([parsed.netloc], index=index)
-    elif dbtype == 'resultdb':
+    if dbtype == 'resultdb':
         from .elasticsearch.resultdb import ResultDB
         return ResultDB([parsed.netloc], index=index)
-    elif dbtype == 'taskdb':
+    if dbtype == 'taskdb':
         from .elasticsearch.taskdb import TaskDB
         return TaskDB([parsed.netloc], index=index)
 
@@ -220,11 +208,10 @@ def _connect_couchdb(parsed, dbtype, url):
     if dbtype == 'taskdb':
         from .couchdb.taskdb import TaskDB
         return TaskDB(url, **params)
-    elif dbtype == 'projectdb':
+    if dbtype == 'projectdb':
         from .couchdb.projectdb import ProjectDB
         return ProjectDB(url, **params)
-    elif dbtype == 'resultdb':
+    if dbtype == 'resultdb':
         from .couchdb.resultdb import ResultDB
         return ResultDB(url, **params)
-    else:
-        raise LookupError
+    raise LookupError
diff --git a/pyspider/database/base/projectdb.py b/pyspider/database/base/projectdb.py
index 7f02c7426..e0e920834 100644
--- a/pyspider/database/base/projectdb.py
+++ b/pyspider/database/base/projectdb.py
@@ -25,7 +25,7 @@
 }
 
 
-class ProjectDB(object):
+class ProjectDB():
     status_str = [
         'TODO',
         'STOP',
@@ -55,8 +55,7 @@ def check_update(self, timestamp, fields=None):
     def split_group(self, group, lower=True):
         if lower:
             return re.split("\W+", (group or '').lower())
-        else:
-            return re.split("\W+", group or '')
+        return re.split("\W+", group or '')
 
     def verify_project_name(self, name):
         if len(name) > 64:
diff --git a/pyspider/database/base/resultdb.py b/pyspider/database/base/resultdb.py
index aa29afd35..c80bff6de 100644
--- a/pyspider/database/base/resultdb.py
+++ b/pyspider/database/base/resultdb.py
@@ -17,7 +17,7 @@
 }
 
 
-class ResultDB(object):
+class ResultDB():
     """
     database for result
     """
diff --git a/pyspider/database/base/taskdb.py b/pyspider/database/base/taskdb.py
index b698a8210..d9703a9e7 100644
--- a/pyspider/database/base/taskdb.py
+++ b/pyspider/database/base/taskdb.py
@@ -56,7 +56,7 @@
 }
 
 
-class TaskDB(object):
+class TaskDB():
     ACTIVE = 1
     SUCCESS = 2
     FAILED = 3
diff --git a/pyspider/database/basedb.py b/pyspider/database/basedb.py
index ca71d6d2c..b471220d5 100644
--- a/pyspider/database/basedb.py
+++ b/pyspider/database/basedb.py
@@ -8,10 +8,9 @@
 from __future__ import unicode_literals, division, absolute_import
 
 import logging
-logger = logging.getLogger('database.basedb')
-
 from six import itervalues
 from pyspider.libs import utils
+logger = logging.getLogger('database.basedb')
 
 
 class BaseDB:
diff --git a/pyspider/database/couchdb/couchdbbase.py b/pyspider/database/couchdb/couchdbbase.py
index 13eb7fb57..244bf165a 100644
--- a/pyspider/database/couchdb/couchdbbase.py
+++ b/pyspider/database/couchdb/couchdbbase.py
@@ -1,7 +1,9 @@
-import time, requests, json
+import time
+
+import requests
 from requests.auth import HTTPBasicAuth
 
-class SplitTableMixin(object):
+class SplitTableMixin():
     UPDATE_PROJECTS_TIME = 10 * 60
 
     def __init__(self):
@@ -13,8 +15,7 @@ def __init__(self):
     def _collection_name(self, project):
         if self.collection_prefix:
             return "%s_%s" % (self.collection_prefix, project)
-        else:
-            return project
+        return project
 
 
     @property
@@ -92,4 +93,3 @@ def update_doc(self, db_name, doc_id, new_doc):
 
     def delete(self, url):
         return self.session.delete(url).json()
-
diff --git a/pyspider/database/couchdb/projectdb.py b/pyspider/database/couchdb/projectdb.py
index 17c1f6ff3..e0201f3d1 100644
--- a/pyspider/database/couchdb/projectdb.py
+++ b/pyspider/database/couchdb/projectdb.py
@@ -1,4 +1,5 @@
-import time, requests, json
+import time
+import requests
 from requests.auth import HTTPBasicAuth
 from pyspider.database.base.projectdb import ProjectDB as BaseProjectDB
 
diff --git a/pyspider/database/couchdb/resultdb.py b/pyspider/database/couchdb/resultdb.py
index 163a6c17b..f9fde979f 100644
--- a/pyspider/database/couchdb/resultdb.py
+++ b/pyspider/database/couchdb/resultdb.py
@@ -1,4 +1,4 @@
-import time, json
+import time
 from pyspider.database.base.resultdb import ResultDB as BaseResultDB
 from .couchdbbase import SplitTableMixin
 
@@ -105,4 +105,4 @@ def drop(self, project):
         # drop the project
         collection_name = self._get_collection_name(project)
         url = self.base_url + collection_name
-        return self.delete(url)
\ No newline at end of file
+        return self.delete(url)
diff --git a/pyspider/database/couchdb/taskdb.py b/pyspider/database/couchdb/taskdb.py
index 9110be82a..ae9b8afe3 100644
--- a/pyspider/database/couchdb/taskdb.py
+++ b/pyspider/database/couchdb/taskdb.py
@@ -1,4 +1,4 @@
-import json, time
+import time
 from pyspider.database.base.taskdb import TaskDB as BaseTaskDB
 from .couchdbbase import SplitTableMixin
 
@@ -107,4 +107,4 @@ def drop_database(self):
     def drop(self, project):
         collection_name = self._get_collection_name(project)
         url = self.base_url + collection_name
-        return self.delete(url)
\ No newline at end of file
+        return self.delete(url)
diff --git a/pyspider/database/local/projectdb.py b/pyspider/database/local/projectdb.py
index 835fe5a56..22dafb13b 100644
--- a/pyspider/database/local/projectdb.py
+++ b/pyspider/database/local/projectdb.py
@@ -7,9 +7,10 @@
 
 import os
 import re
-import six
 import glob
 import logging
+import six
+
 
 from pyspider.database.base.projectdb import ProjectDB as BaseProjectDB
 
@@ -44,7 +45,7 @@ def load_scripts(self):
 
     def _build_project(self, filename):
         try:
-            with open(filename) as fp:
+            with open(filename, encoding='utf-8') as fp:
                 script = fp.read()
             m = self.rate_re.search(script)
             if m:
diff --git a/pyspider/database/mongodb/mongodbbase.py b/pyspider/database/mongodb/mongodbbase.py
index 5815904b3..bd6b248d9 100644
--- a/pyspider/database/mongodb/mongodbbase.py
+++ b/pyspider/database/mongodb/mongodbbase.py
@@ -8,14 +8,13 @@
 import time
 
 
-class SplitTableMixin(object):
+class SplitTableMixin():
     UPDATE_PROJECTS_TIME = 10 * 60
 
     def _collection_name(self, project):
         if self.collection_prefix:
             return "%s.%s" % (self.collection_prefix, project)
-        else:
-            return project
+        return project
 
     @property
     def projects(self):
diff --git a/pyspider/database/mysql/mysqlbase.py b/pyspider/database/mysql/mysqlbase.py
index 9dfc1aa0e..a23afc63b 100644
--- a/pyspider/database/mysql/mysqlbase.py
+++ b/pyspider/database/mysql/mysqlbase.py
@@ -9,7 +9,7 @@
 import mysql.connector
 
 
-class MySQLMixin(object):
+class MySQLMixin():
     maxlimit = 18446744073709551615
 
     @property
@@ -26,14 +26,13 @@ def dbcur(self):
             return self.conn.cursor()
 
 
-class SplitTableMixin(object):
+class SplitTableMixin():
     UPDATE_PROJECTS_TIME = 10 * 60
 
     def _tablename(self, project):
         if self.__tablename__:
             return '%s_%s' % (self.__tablename__, project)
-        else:
-            return project
+        return project
 
     @property
     def projects(self):
diff --git a/pyspider/database/mysql/resultdb.py b/pyspider/database/mysql/resultdb.py
index 3fb50b68f..e1f8cb968 100644
--- a/pyspider/database/mysql/resultdb.py
+++ b/pyspider/database/mysql/resultdb.py
@@ -6,9 +6,9 @@
 # Created on 2014-10-13 22:02:57
 
 import re
-import six
 import time
 import json
+import six
 import mysql.connector
 
 from pyspider.libs import utils
diff --git a/pyspider/database/mysql/taskdb.py b/pyspider/database/mysql/taskdb.py
index 90e97a8ac..8764f8245 100644
--- a/pyspider/database/mysql/taskdb.py
+++ b/pyspider/database/mysql/taskdb.py
@@ -7,9 +7,10 @@
 
 
 import re
-import six
 import time
 import json
+import six
+
 import mysql.connector
 
 from pyspider.libs import utils
@@ -97,7 +98,7 @@ def get_task(self, project, taskid, fields=None):
         return None
 
     def status_count(self, project):
-        result = dict()
+        result = {}
         if project not in self.projects:
             self._list_project()
         if project not in self.projects:
diff --git a/pyspider/database/redis/__init__.py b/pyspider/database/redis/__init__.py
index 181c4e734..043e3b3f3 100644
--- a/pyspider/database/redis/__init__.py
+++ b/pyspider/database/redis/__init__.py
@@ -4,4 +4,3 @@
 # Author: Binux<roy@binux.me>
 #         http://binux.me
 # Created on 2015-05-17 01:34:21
-
diff --git a/pyspider/database/redis/taskdb.py b/pyspider/database/redis/taskdb.py
index c6125b6ea..b9de5a340 100644
--- a/pyspider/database/redis/taskdb.py
+++ b/pyspider/database/redis/taskdb.py
@@ -5,12 +5,12 @@
 #         http://binux.me
 # Created on 2015-05-16 21:01:52
 
-import six
 import time
 import json
-import redis
 import logging
 import itertools
+import redis
+import six
 
 from pyspider.libs import utils
 from pyspider.database.base.taskdb import TaskDB as BaseTaskDB
@@ -99,8 +99,7 @@ def get_method(key):
                 if not obj:
                     #self.redis.srem(status_key, taskid)
                     continue
-                else:
-                    yield self._parse(obj)
+                yield self._parse(obj)
 
     def get_task(self, project, taskid, fields=None):
         if fields:
diff --git a/pyspider/database/sqlalchemy/__init__.py b/pyspider/database/sqlalchemy/__init__.py
index d0548d60e..204a4da10 100644
--- a/pyspider/database/sqlalchemy/__init__.py
+++ b/pyspider/database/sqlalchemy/__init__.py
@@ -4,4 +4,3 @@
 # Author: Binux<roy@binux.me>
 #         http://binux.me
 # Created on 2014-12-04 20:11:04
-
diff --git a/pyspider/database/sqlalchemy/projectdb.py b/pyspider/database/sqlalchemy/projectdb.py
index 18e323c1d..c4be1fd1e 100644
--- a/pyspider/database/sqlalchemy/projectdb.py
+++ b/pyspider/database/sqlalchemy/projectdb.py
@@ -5,13 +5,11 @@
 #         http://binux.me
 # Created on 2014-12-04 23:25:10
 
-import six
 import time
 import sqlalchemy.exc
 
 from sqlalchemy import create_engine, MetaData, Table, Column, String, Float, Text
 from sqlalchemy.engine.url import make_url
-from pyspider.libs import utils
 from pyspider.database.base.projectdb import ProjectDB as BaseProjectDB
 from .sqlalchemybase import result2dict
 
diff --git a/pyspider/database/sqlalchemy/resultdb.py b/pyspider/database/sqlalchemy/resultdb.py
index 8f91f6b49..e9c7c0a9f 100644
--- a/pyspider/database/sqlalchemy/resultdb.py
+++ b/pyspider/database/sqlalchemy/resultdb.py
@@ -6,9 +6,9 @@
 # Created on 2014-12-04 18:48:15
 
 import re
-import six
 import time
 import json
+import six
 import sqlalchemy.exc
 
 from sqlalchemy import (create_engine, MetaData, Table, Column,
@@ -93,9 +93,8 @@ def save(self, project, taskid, url, result):
             return self.engine.execute(self.table.update()
                                        .where(self.table.c.taskid == taskid)
                                        .values(**self._stringify(obj)))
-        else:
-            return self.engine.execute(self.table.insert()
-                                       .values(**self._stringify(obj)))
+        return self.engine.execute(self.table.insert()
+                                   .values(**self._stringify(obj)))
 
     def select(self, project, fields=None, offset=0, limit=None):
         if project not in self.projects:
diff --git a/pyspider/database/sqlalchemy/sqlalchemybase.py b/pyspider/database/sqlalchemy/sqlalchemybase.py
index 8fc100d21..411633542 100644
--- a/pyspider/database/sqlalchemy/sqlalchemybase.py
+++ b/pyspider/database/sqlalchemy/sqlalchemybase.py
@@ -12,14 +12,13 @@ def result2dict(columns, task):
     return dict(task)
 
 
-class SplitTableMixin(object):
+class SplitTableMixin():
     UPDATE_PROJECTS_TIME = 10 * 60
 
     def _tablename(self, project):
         if self.__tablename__:
             return '%s_%s' % (self.__tablename__, project)
-        else:
-            return project
+        return project
 
     @property
     def projects(self):
diff --git a/pyspider/database/sqlalchemy/taskdb.py b/pyspider/database/sqlalchemy/taskdb.py
index b298d608b..04834f8ce 100644
--- a/pyspider/database/sqlalchemy/taskdb.py
+++ b/pyspider/database/sqlalchemy/taskdb.py
@@ -6,9 +6,10 @@
 # Created on 2014-12-04 22:33:43
 
 import re
-import six
 import time
 import json
+import six
+
 import sqlalchemy.exc
 
 from sqlalchemy import (create_engine, MetaData, Table, Column, Index,
@@ -118,7 +119,7 @@ def get_task(self, project, taskid, fields=None):
             return self._parse(result2dict(columns, each))
 
     def status_count(self, project):
-        result = dict()
+        result = {}
         if project not in self.projects:
             self._list_project()
         if project not in self.projects:
diff --git a/pyspider/database/sqlite/projectdb.py b/pyspider/database/sqlite/projectdb.py
index 282ce5305..de8f92491 100644
--- a/pyspider/database/sqlite/projectdb.py
+++ b/pyspider/database/sqlite/projectdb.py
@@ -7,9 +7,10 @@
 
 import time
 
-from .sqlitebase import SQLiteMixin
 from pyspider.database.base.projectdb import ProjectDB as BaseProjectDB
 from pyspider.database.basedb import BaseDB
+from .sqlitebase import SQLiteMixin
+
 
 
 class ProjectDB(SQLiteMixin, BaseProjectDB, BaseDB):
diff --git a/pyspider/database/sqlite/resultdb.py b/pyspider/database/sqlite/resultdb.py
index 0314eaf2d..5b51123f9 100644
--- a/pyspider/database/sqlite/resultdb.py
+++ b/pyspider/database/sqlite/resultdb.py
@@ -9,9 +9,9 @@
 import time
 import json
 
-from .sqlitebase import SQLiteMixin, SplitTableMixin
 from pyspider.database.base.resultdb import ResultDB as BaseResultDB
 from pyspider.database.basedb import BaseDB
+from .sqlitebase import SQLiteMixin, SplitTableMixin
 
 
 class ResultDB(SQLiteMixin, SplitTableMixin, BaseResultDB, BaseDB):
diff --git a/pyspider/database/sqlite/sqlitebase.py b/pyspider/database/sqlite/sqlitebase.py
index 9a652b9f7..0a64d594b 100644
--- a/pyspider/database/sqlite/sqlitebase.py
+++ b/pyspider/database/sqlite/sqlitebase.py
@@ -11,7 +11,7 @@
 import threading
 
 
-class SQLiteMixin(object):
+class SQLiteMixin():
 
     @property
     def dbcur(self):
@@ -22,14 +22,13 @@ def dbcur(self):
         return self.conn.cursor()
 
 
-class SplitTableMixin(object):
+class SplitTableMixin():
     UPDATE_PROJECTS_TIME = 10 * 60
 
     def _tablename(self, project):
         if self.__tablename__:
             return '%s_%s' % (self.__tablename__, project)
-        else:
-            return project
+        return project
 
     @property
     def projects(self):
diff --git a/pyspider/database/sqlite/taskdb.py b/pyspider/database/sqlite/taskdb.py
index 5a0095d5a..9fab15ffa 100644
--- a/pyspider/database/sqlite/taskdb.py
+++ b/pyspider/database/sqlite/taskdb.py
@@ -9,9 +9,10 @@
 import time
 import json
 
-from .sqlitebase import SQLiteMixin, SplitTableMixin
 from pyspider.database.base.taskdb import TaskDB as BaseTaskDB
 from pyspider.database.basedb import BaseDB
+from .sqlitebase import SQLiteMixin, SplitTableMixin
+
 
 
 class TaskDB(SQLiteMixin, SplitTableMixin, BaseTaskDB, BaseDB):
@@ -86,7 +87,7 @@ def status_count(self, project):
         '''
         return a dict
         '''
-        result = dict()
+        result = {}
         if project not in self.projects:
             self._list_project()
         if project not in self.projects:
diff --git a/pyspider/fetcher/cookie_utils.py b/pyspider/fetcher/cookie_utils.py
index e486fa8af..a57320c8a 100644
--- a/pyspider/fetcher/cookie_utils.py
+++ b/pyspider/fetcher/cookie_utils.py
@@ -8,7 +8,7 @@
 from requests.cookies import MockRequest
 
 
-class MockResponse(object):
+class MockResponse():
 
     def __init__(self, headers):
         self._headers = headers
diff --git a/pyspider/fetcher/tornado_fetcher.py b/pyspider/fetcher/tornado_fetcher.py
index d64169351..71b87d4b1 100644
--- a/pyspider/fetcher/tornado_fetcher.py
+++ b/pyspider/fetcher/tornado_fetcher.py
@@ -9,7 +9,6 @@
 
 import os
 import sys
-import six
 import copy
 import time
 import json
@@ -17,19 +16,22 @@
 import traceback
 import functools
 import threading
+import six
 import tornado.ioloop
 import tornado.httputil
 import tornado.httpclient
-import pyspider
 
 from six.moves import queue, http_cookies
 from six.moves.urllib.robotparser import RobotFileParser
-from requests import cookies
 from six.moves.urllib.parse import urljoin, urlsplit
+from requests import cookies
+
 from tornado import gen
 from tornado.curl_httpclient import CurlAsyncHTTPClient
 from tornado.simple_httpclient import SimpleAsyncHTTPClient
 
+import pyspider
+
 from pyspider.libs import utils, dataurl, counter
 from pyspider.libs.url import quote_chinese
 from .cookie_utils import extract_cookies_to_jar
@@ -63,7 +65,7 @@ def size(self):
 }
 
 
-class Fetcher(object):
+class Fetcher():
     user_agent = "pyspider/%s (+http://pyspider.org/)" % pyspider.__version__
     default_options = {
         'method': 'GET',
@@ -75,7 +77,7 @@ class Fetcher(object):
     }
     phantomjs_proxy = None
     splash_endpoint = None
-    splash_lua_source = open(os.path.join(os.path.dirname(__file__), "splash_fetcher.lua")).read()
+    splash_lua_source = open(os.path.join(os.path.dirname(__file__), "splash_fetcher.lua"), encoding='utf-8').read()
     robot_txt_age = 60*60  # 1h
 
     def __init__(self, inqueue, outqueue, poolsize=100, proxy=None, async_mode=True):
@@ -116,8 +118,7 @@ def send_result(self, type, task, result):
     def fetch(self, task, callback=None):
         if self.async_mode:
             return self.async_fetch(task, callback)
-        else:
-            return self.async_fetch(task, callback).result()
+        return self.async_fetch(task, callback).result()
 
     @gen.coroutine
     def async_fetch(self, task, callback=None):
diff --git a/pyspider/libs/ListIO.py b/pyspider/libs/ListIO.py
index e48d42edd..b9d5bd4bb 100644
--- a/pyspider/libs/ListIO.py
+++ b/pyspider/libs/ListIO.py
@@ -6,7 +6,7 @@
 # Created on 2014-02-26 23:41:51
 
 
-class ListO(object):
+class ListO():
 
     """A StringO write to list."""
 
diff --git a/pyspider/libs/base_handler.py b/pyspider/libs/base_handler.py
index d2ebe9584..39745555a 100644
--- a/pyspider/libs/base_handler.py
+++ b/pyspider/libs/base_handler.py
@@ -61,7 +61,7 @@ def wrapper(func):
     return wrapper
 
 
-class NOTSET(object):
+class NOTSET():
     pass
 
 
@@ -120,7 +120,7 @@ def __new__(cls, name, bases, attrs):
 
 
 @add_metaclass(BaseHandlerMeta)
-class BaseHandler(object):
+class BaseHandler():
     """
     BaseHandler for all scripts.
 
@@ -391,7 +391,7 @@ def crawl(self, url, **kwargs):
 
         if isinstance(url, six.string_types):
             return self._crawl(url, **kwargs)
-        elif hasattr(url, "__iter__"):
+        if hasattr(url, "__iter__"):
             result = []
             for each in url:
                 result.append(self._crawl(each, **kwargs))
diff --git a/pyspider/libs/bench.py b/pyspider/libs/bench.py
index 9e7bfd6e9..c9400c24c 100644
--- a/pyspider/libs/bench.py
+++ b/pyspider/libs/bench.py
@@ -9,7 +9,6 @@
 
 import time
 import logging
-logger = logging.getLogger('bench')
 
 from six.moves import queue as Queue
 from pyspider.scheduler import ThreadBaseScheduler as Scheduler
@@ -18,6 +17,8 @@
 from pyspider.result import ResultWorker
 from pyspider.libs.utils import md5string
 
+logger = logging.getLogger('bench')
+
 
 def bench_test_taskdb(taskdb):
     project_name = '__bench_test__'
@@ -187,7 +188,7 @@ def test_get(n):
             pass
 
 
-class BenchMixin(object):
+class BenchMixin():
     """Report to logger for bench test"""
     def _bench_init(self):
         self.done_cnt = 0
@@ -212,42 +213,42 @@ def _bench_report(self, name, prefix=0, rjust=0):
 
 class BenchScheduler(Scheduler, BenchMixin):
     def __init__(self, *args, **kwargs):
-        super(BenchScheduler, self).__init__(*args, **kwargs)
+        super().__init__(*args, **kwargs)
         self._bench_init()
 
     def on_task_status(self, task):
         self._bench_report('Crawled')
-        return super(BenchScheduler, self).on_task_status(task)
+        return super().on_task_status(task)
 
 
 class BenchFetcher(Fetcher, BenchMixin):
     def __init__(self, *args, **kwargs):
-        super(BenchFetcher, self).__init__(*args, **kwargs)
+        super().__init__(*args, **kwargs)
         self._bench_init()
 
     def on_result(self, type, task, result):
         self._bench_report("Fetched", 0, 75)
-        return super(BenchFetcher, self).on_result(type, task, result)
+        return super().on_result(type, task, result)
 
 
 class BenchProcessor(Processor, BenchMixin):
     def __init__(self, *args, **kwargs):
-        super(BenchProcessor, self).__init__(*args, **kwargs)
+        super().__init__(*args, **kwargs)
         self._bench_init()
 
     def on_task(self, task, response):
         self._bench_report("Processed", 75)
-        return super(BenchProcessor, self).on_task(task, response)
+        return super().on_task(task, response)
 
 
 class BenchResultWorker(ResultWorker, BenchMixin):
     def __init__(self, *args, **kwargs):
-        super(BenchResultWorker, self).__init__(*args, **kwargs)
+        super().__init__(*args, **kwargs)
         self._bench_init()
 
     def on_result(self, task, result):
         self._bench_report("Saved", 0, 150)
-        super(BenchResultWorker, self).on_result(task, result)
+        super().on_result(task, result)
 
 
 from pyspider.libs.base_handler import BaseHandler
diff --git a/pyspider/libs/counter.py b/pyspider/libs/counter.py
index 88ff60eeb..265ee889e 100644
--- a/pyspider/libs/counter.py
+++ b/pyspider/libs/counter.py
@@ -13,14 +13,14 @@
 try:
     from UserDict import DictMixin
 except ImportError:
-    from collections import Mapping as DictMixin
+    from collections.abc import Mapping as DictMixin
 
 import six
 from six import iteritems
 from six.moves import cPickle
 
 
-class BaseCounter(object):
+class BaseCounter():
 
     def __init__(self):
         pass
@@ -52,7 +52,7 @@ class TotalCounter(BaseCounter):
     """Total counter"""
 
     def __init__(self):
-        super(TotalCounter, self).__init__()
+        super().__init__()
         self.cnt = 0
 
     def event(self, value=1):
@@ -79,7 +79,7 @@ class AverageWindowCounter(BaseCounter):
     """
 
     def __init__(self, window_size=300):
-        super(AverageWindowCounter, self).__init__()
+        super().__init__()
         self.window_size = window_size
         self.values = deque(maxlen=window_size)
 
@@ -109,7 +109,7 @@ class TimebaseAverageEventCounter(BaseCounter):
     """
 
     def __init__(self, window_size=30, window_interval=10):
-        super(TimebaseAverageEventCounter, self).__init__()
+        super().__init__()
         self.max_window_size = window_size
         self.window_size = 0
         self.window_interval = window_interval
@@ -195,7 +195,7 @@ class TimebaseAverageWindowCounter(BaseCounter):
     """
 
     def __init__(self, window_size=30, window_interval=10):
-        super(TimebaseAverageWindowCounter, self).__init__()
+        super().__init__()
         self.max_window_size = window_size
         self.window_size = 0
         self.window_interval = window_interval
@@ -278,8 +278,7 @@ def __getitem__(self, key):
         if key == '__value__':
             key = self._keys
             return self.manager.counters[key]
-        else:
-            key = self._keys + (key, )
+        key = self._keys + (key, )
 
         available_keys = []
         for _key in list(self.manager.counters.keys()):
@@ -288,13 +287,11 @@ def __getitem__(self, key):
 
         if len(available_keys) == 0:
             raise KeyError
-        elif len(available_keys) == 1:
+        if len(available_keys) == 1:
             if available_keys[0] == key:
                 return self.manager.counters.get(key)
-            else:
-                return CounterValue(self.manager, key)
-        else:
             return CounterValue(self.manager, key)
+        return CounterValue(self.manager, key)
 
     def __len__(self):
         return len(self.keys())
@@ -378,13 +375,11 @@ def __getitem__(self, key):
 
         if len(available_keys) == 0:
             raise KeyError
-        elif len(available_keys) == 1:
+        if len(available_keys) == 1:
             if available_keys[0] == key:
                 return self.counters.get(key)
-            else:
-                return CounterValue(self, key)
-        else:
             return CounterValue(self, key)
+        return CounterValue(self, key)
 
     def __delitem__(self, key):
         key = (key, )
@@ -435,7 +430,7 @@ def load(self, filename):
         try:
             with open(filename, 'rb') as fp:
                 self.counters = cPickle.load(fp)
-        except:
+        except Exception:
             logging.debug("can't load counter from file: %s", filename)
             return False
         return True
diff --git a/pyspider/libs/dataurl.py b/pyspider/libs/dataurl.py
index 3f75095e4..47d84a20e 100644
--- a/pyspider/libs/dataurl.py
+++ b/pyspider/libs/dataurl.py
@@ -5,10 +5,11 @@
 #         http://binux.me
 # Created on 2012-11-16 10:33:20
 
-import six
 from base64 import b64encode, b64decode
-from . import utils
+import six
 from six.moves.urllib.parse import quote, unquote
+from . import utils
+
 
 
 def encode(data, mime_type='', charset='utf-8', base64=True):
diff --git a/pyspider/libs/log.py b/pyspider/libs/log.py
index 770ff20f4..d2b468792 100644
--- a/pyspider/libs/log.py
+++ b/pyspider/libs/log.py
@@ -15,12 +15,12 @@
 from tornado.log import LogFormatter as _LogFormatter
 
 
-class LogFormatter(_LogFormatter, object):
+class LogFormatter(_LogFormatter):
     """Init tornado.log.LogFormatter from logging.config.fileConfig"""
     def __init__(self, fmt=None, datefmt=None, color=True, *args, **kwargs):
         if fmt is None:
             fmt = _LogFormatter.DEFAULT_FORMAT
-        super(LogFormatter, self).__init__(color=color, fmt=fmt, *args, **kwargs)
+        super().__init__(color=color, fmt=fmt, *args, **kwargs)
 
 
 class SaveLogHandler(logging.Handler):
diff --git a/pyspider/libs/multiprocessing_queue.py b/pyspider/libs/multiprocessing_queue.py
index 96525225e..b627035ab 100644
--- a/pyspider/libs/multiprocessing_queue.py
+++ b/pyspider/libs/multiprocessing_queue.py
@@ -1,4 +1,3 @@
-import six
 import platform
 import multiprocessing
 from multiprocessing.queues import Queue as BaseQueue
@@ -7,7 +6,7 @@
 # The SharedCounter and Queue classes come from:
 # https://github.com/vterron/lemon/commit/9ca6b4b
 
-class SharedCounter(object):
+class SharedCounter():
     """ A synchronized shared counter.
     The locking done by multiprocessing.Value ensures that only a single
     process or thread may read or write the in-memory ctypes object. However,
@@ -45,15 +44,15 @@ class MultiProcessingQueue(BaseQueue):
     qsize() and empty().
     """
     def __init__(self, *args, **kwargs):
-        super(MultiProcessingQueue, self).__init__(*args, **kwargs)
+        super().__init__(*args, **kwargs)
         self.size = SharedCounter(0)
 
     def put(self, *args, **kwargs):
         self.size.increment(1)
-        super(MultiProcessingQueue, self).put(*args, **kwargs)
+        super().put(*args, **kwargs)
 
     def get(self, *args, **kwargs):
-        v = super(MultiProcessingQueue, self).get(*args, **kwargs)
+        v = super().get(*args, **kwargs)
         self.size.increment(-1)
         return v
 
diff --git a/pyspider/libs/pprint.py b/pyspider/libs/pprint.py
index 0ff21716e..63596c53d 100644
--- a/pyspider/libs/pprint.py
+++ b/pyspider/libs/pprint.py
@@ -36,10 +36,11 @@
 
 from __future__ import print_function
 
-import six
+
 import sys as _sys
 
 from io import BytesIO, StringIO
+import six
 
 __all__ = ["pprint", "pformat", "isreadable", "isrecursive", "saferepr",
            "PrettyPrinter"]
@@ -268,7 +269,7 @@ def _safe_repr(object, context, maxlevels, level):
         try:
             string.decode('utf8').encode('gbk', 'replace')
             return ("%s%s%s" % (closure, string, closure)), True, False
-        except:
+        except Exception:
             pass
         qget = quotes.get
         sio = StringIO()
diff --git a/pyspider/libs/response.py b/pyspider/libs/response.py
index 8975781b2..ae2a4a248 100644
--- a/pyspider/libs/response.py
+++ b/pyspider/libs/response.py
@@ -7,8 +7,9 @@
 
 import cgi
 import re
-import six
 import json
+import six
+
 import chardet
 import lxml.html
 import lxml.etree
@@ -19,7 +20,7 @@
 from pyspider.libs import utils
 
 
-class Response(object):
+class Response():
 
     def __init__(self, status_code=None, url=None, orig_url=None, headers=CaseInsensitiveDict(),
                  content='', cookies=None, error=None, traceback=None, save=None, js_script_result=None, time=0):
@@ -38,7 +39,7 @@ def __init__(self, status_code=None, url=None, orig_url=None, headers=CaseInsens
         self.time = time
 
     def __repr__(self):
-        return u'<Response [%d]>' % self.status_code
+        return '<Response [%d]>' % self.status_code
 
     def __bool__(self):
         """Returns true if `status_code` is 200 and no error"""
@@ -53,7 +54,7 @@ def ok(self):
         """Return true if `status_code` is 200 and no error."""
         try:
             self.raise_for_status()
-        except:
+        except Exception:
             return False
         return True
 
@@ -105,7 +106,7 @@ def text(self):
         if hasattr(self, '_text') and self._text:
             return self._text
         if not self.content:
-            return u''
+            return ''
         if isinstance(self.content, six.text_type):
             return self.content
 
@@ -167,7 +168,7 @@ def raise_for_status(self, allow_redirects=True):
 
         if self.status_code == 304:
             return
-        elif self.error:
+        if self.error:
             if self.traceback:
                 six.reraise(Exception, Exception(self.error), Traceback.from_string(self.traceback).as_traceback())
             http_error = HTTPError(self.error)
@@ -187,7 +188,7 @@ def isok(self):
         try:
             self.raise_for_status()
             return True
-        except:
+        except Exception:
             return False
 
 
diff --git a/pyspider/libs/result_dump.py b/pyspider/libs/result_dump.py
index 5e7dd45a6..29d4e8c77 100644
--- a/pyspider/libs/result_dump.py
+++ b/pyspider/libs/result_dump.py
@@ -5,11 +5,11 @@
 #         http://binux.me
 # Created on 2015-03-27 20:12:11
 
-import six
 import csv
 import json
 import itertools
 from io import StringIO, BytesIO
+import six
 from six import iteritems
 
 
@@ -74,18 +74,14 @@ def toString(obj):
         if isinstance(obj, six.binary_type):
             if six.PY2:
                 return obj
-            else:
-                return obj.decode('utf8')
-        elif isinstance(obj, six.text_type):
+            return obj.decode('utf8')
+        if isinstance(obj, six.text_type):
             if six.PY2:
                 return obj.encode('utf8')
-            else:
-                return obj
-        else:
-            if six.PY2:
-                return json.dumps(obj, ensure_ascii=False).encode('utf8')
-            else:
-                return json.dumps(obj, ensure_ascii=False)
+            return obj
+        if six.PY2:
+            return json.dumps(obj, ensure_ascii=False).encode('utf8')
+        return json.dumps(obj, ensure_ascii=False)
 
     # python2 needs byes when python3 needs unicode
     if six.PY2:
diff --git a/pyspider/libs/url.py b/pyspider/libs/url.py
index c1c99a59f..8d82b85f4 100644
--- a/pyspider/libs/url.py
+++ b/pyspider/libs/url.py
@@ -7,8 +7,8 @@
 
 import mimetypes
 
-import six
 import shlex
+import six
 from six.moves.urllib.parse import urlparse, urlunparse
 from requests.models import RequestEncodingMixin
 
@@ -94,7 +94,7 @@ def curl_to_arguments(curl):
             # option
             if current_opt is None:
                 raise TypeError('Unknow curl argument: %s' % part)
-            elif current_opt in ('-H', '--header'):
+            if current_opt in ('-H', '--header'):
                 key_value = part.split(':', 1)
                 if len(key_value) == 2:
                     key, value = key_value
diff --git a/pyspider/libs/utils.py b/pyspider/libs/utils.py
index 336021a03..3961d98ee 100644
--- a/pyspider/libs/utils.py
+++ b/pyspider/libs/utils.py
@@ -31,7 +31,7 @@ def getitem(obj, key=0, default=None):
     """Get first element of list or return default"""
     try:
         return obj[key]
-    except:
+    except Exception:
         return default
 
 
@@ -111,8 +111,7 @@ def format_date(date, gmt_offset=0, relative=True, shorter=False, full_format=Fa
         format = fff_format
         if ret_:
             return format
-        else:
-            format = format
+        format = format
 
     if format is None:
         format = "%(month_name)s %(day)s, %(year)s" if shorter else \
@@ -218,10 +217,9 @@ def utf8(string):
     """
     if isinstance(string, six.text_type):
         return string.encode('utf8')
-    elif isinstance(string, six.binary_type):
+    if isinstance(string, six.binary_type):
         return string
-    else:
-        return six.text_type(string).encode('utf8')
+    return six.text_type(string).encode('utf8')
 
 
 def text(string, encoding='utf8'):
@@ -232,10 +230,9 @@ def text(string, encoding='utf8'):
     """
     if isinstance(string, six.text_type):
         return string
-    elif isinstance(string, six.binary_type):
+    if isinstance(string, six.binary_type):
         return string.decode(encoding)
-    else:
-        return six.text_type(string)
+    return six.text_type(string)
 
 
 def pretty_unicode(string):
@@ -289,19 +286,18 @@ def unicode_obj(obj):
     """
     if isinstance(obj, dict):
         return unicode_dict(obj)
-    elif isinstance(obj, (list, tuple)):
+    if isinstance(obj, (list, tuple)):
         return unicode_list(obj)
-    elif isinstance(obj, six.string_types):
+    if isinstance(obj, six.string_types):
         return unicode_string(obj)
-    elif isinstance(obj, (int, float)):
+    if isinstance(obj, (int, float)):
         return obj
-    elif obj is None:
+    if obj is None:
         return obj
-    else:
-        try:
-            return text(obj)
-        except:
-            return text(repr(obj))
+    try:
+        return text(obj)
+    except Exception:
+        return text(repr(obj))
 
 
 def decode_unicode_string(string):
@@ -322,15 +318,14 @@ def decode_unicode_obj(obj):
         for k, v in iteritems(obj):
             r[decode_unicode_string(k)] = decode_unicode_obj(v)
         return r
-    elif isinstance(obj, six.string_types):
+    if isinstance(obj, six.string_types):
         return decode_unicode_string(obj)
-    elif isinstance(obj, (list, tuple)):
+    if isinstance(obj, (list, tuple)):
         return [decode_unicode_obj(x) for x in obj]
-    else:
-        return obj
+    return obj
 
 
-class Get(object):
+class Get():
     """
     Lazy value calculate for object
     """
@@ -434,7 +429,4 @@ def python_console(namespace=None):
 def check_port_open(port, addr='127.0.0.1'):
     with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as sock:
         result = sock.connect_ex((addr, port))
-        if result == 0:
-            return True
-        else:
-            return False
+        return result == 0
diff --git a/pyspider/libs/wsgi_xmlrpc.py b/pyspider/libs/wsgi_xmlrpc.py
index 37b6eafa4..3654b118b 100644
--- a/pyspider/libs/wsgi_xmlrpc.py
+++ b/pyspider/libs/wsgi_xmlrpc.py
@@ -15,13 +15,14 @@
 #   Origin: https://code.google.com/p/wsgi-xmlrpc/
 
 
-from six.moves.xmlrpc_server import SimpleXMLRPCDispatcher
 import logging
+from six.moves.xmlrpc_server import SimpleXMLRPCDispatcher
+
 
 logger = logging.getLogger(__name__)
 
 
-class WSGIXMLRPCApplication(object):
+class WSGIXMLRPCApplication():
     """Application to handle requests to the XMLRPC service"""
 
     def __init__(self, instance=None, methods=None):
@@ -50,9 +51,8 @@ def handler(self, environ, start_response):
 
         if environ['REQUEST_METHOD'] == 'POST':
             return self.handle_POST(environ, start_response)
-        else:
-            start_response("400 Bad request", [('Content-Type', 'text/plain')])
-            return ['']
+        start_response("400 Bad request", [('Content-Type', 'text/plain')])
+        return ['']
 
     def handle_POST(self, environ, start_response):
         """Handles the HTTP POST request.
diff --git a/pyspider/message_queue/__init__.py b/pyspider/message_queue/__init__.py
index 86592f6fb..2ec7a3b7d 100644
--- a/pyspider/message_queue/__init__.py
+++ b/pyspider/message_queue/__init__.py
@@ -41,7 +41,7 @@ def connect_message_queue(name, url=None, maxsize=0, lazy_limit=True):
     if parsed.scheme == 'amqp':
         from .rabbitmq import Queue
         return Queue(name, url, maxsize=maxsize, lazy_limit=lazy_limit)
-    elif parsed.scheme == 'redis':
+    if parsed.scheme == 'redis':
         from .redis_queue import Queue
         if ',' in parsed.netloc:
             """
@@ -53,21 +53,18 @@ def connect_message_queue(name, url=None, maxsize=0, lazy_limit=True):
                 cluster_nodes.append({'host': netloc.split(':')[0], 'port': int(netloc.split(':')[1])})
 
             return Queue(name=name, maxsize=maxsize, lazy_limit=lazy_limit, cluster_nodes=cluster_nodes)
+        db = parsed.path.lstrip('/').split('/')
+        try:
+            db = int(db[0])
+        except Exception:
+            logging.warning('redis DB must zero-based numeric index, using 0 instead')
+            db = 0
 
-        else:
-            db = parsed.path.lstrip('/').split('/')
-            try:
-                db = int(db[0])
-            except:
-                logging.warning('redis DB must zero-based numeric index, using 0 instead')
-                db = 0
+        password = parsed.password or None
 
-            password = parsed.password or None
-
-            return Queue(name=name, host=parsed.hostname, port=parsed.port, db=db, maxsize=maxsize, password=password, lazy_limit=lazy_limit)
-    elif url.startswith('kombu+'):
+        return Queue(name=name, host=parsed.hostname, port=parsed.port, db=db, maxsize=maxsize, password=password, lazy_limit=lazy_limit)
+    if url.startswith('kombu+'):
         url = url[len('kombu+'):]
         from .kombu_queue import Queue
         return Queue(name, url, maxsize=maxsize, lazy_limit=lazy_limit)
-    else:
-        raise Exception('unknown connection url: %s', url)
+    raise Exception('unknown connection url: %s', url)
diff --git a/pyspider/message_queue/kombu_queue.py b/pyspider/message_queue/kombu_queue.py
index e16f7b8c0..035e80ff1 100644
--- a/pyspider/message_queue/kombu_queue.py
+++ b/pyspider/message_queue/kombu_queue.py
@@ -17,7 +17,7 @@
 enable_insecure_serializers(['umsgpack'])
 
 
-class KombuQueue(object):
+class KombuQueue():
     """
     kombu is a high-level interface for multiple message queue backends.
 
@@ -57,14 +57,10 @@ def qsize(self):
     def empty(self):
         if self.qsize() == 0:
             return True
-        else:
-            return False
+        return False
 
     def full(self):
-        if self.maxsize and self.qsize() >= self.maxsize:
-            return True
-        else:
-            return False
+        return self.maxsize and self.qsize() >= self.maxsize
 
     def put(self, obj, block=True, timeout=None):
         if not block:
diff --git a/pyspider/message_queue/rabbitmq.py b/pyspider/message_queue/rabbitmq.py
index 9e4e72595..4af81ef6d 100644
--- a/pyspider/message_queue/rabbitmq.py
+++ b/pyspider/message_queue/rabbitmq.py
@@ -9,15 +9,16 @@
 import socket
 import select
 import logging
-import umsgpack
 import threading
+import umsgpack
 
 import amqp
-from six.moves.urllib.parse import unquote
+
 try:
     from urllib import parse as urlparse
 except ImportError:
     import urlparse
+from six.moves.urllib.parse import unquote
 from six.moves import queue as BaseQueue
 
 
@@ -49,7 +50,7 @@ def wrap(self, *args, **kwargs):
     return wrap
 
 
-class PikaQueue(object):
+class PikaQueue():
     """
     A Queue like rabbitmq connector
     """
@@ -111,14 +112,12 @@ def qsize(self):
     def empty(self):
         if self.qsize() == 0:
             return True
-        else:
-            return False
+        return False
 
     def full(self):
         if self.maxsize and self.qsize() >= self.maxsize:
             return True
-        else:
-            return False
+        return False
 
     @catch_error
     def put(self, obj, block=True, timeout=None):
diff --git a/pyspider/message_queue/redis_queue.py b/pyspider/message_queue/redis_queue.py
index dc24924c1..3c47d78ac 100644
--- a/pyspider/message_queue/redis_queue.py
+++ b/pyspider/message_queue/redis_queue.py
@@ -11,7 +11,7 @@
 from six.moves import queue as BaseQueue
 
 
-class RedisQueue(object):
+class RedisQueue():
     """
     A Queue like message built over redis
     """
@@ -31,7 +31,7 @@ def __init__(self, name, host='localhost', port=6379, db=0,
                     for better performance.
         """
         self.name = name
-        if(cluster_nodes is not None):
+        if cluster_nodes is not None:
             from rediscluster import StrictRedisCluster
             self.redis = StrictRedisCluster(startup_nodes=cluster_nodes)
         else:
@@ -47,14 +47,12 @@ def qsize(self):
     def empty(self):
         if self.qsize() == 0:
             return True
-        else:
-            return False
+        return False
 
     def full(self):
         if self.maxsize and self.qsize() >= self.maxsize:
             return True
-        else:
-            return False
+        return False
 
     def put_nowait(self, obj):
         if self.lazy_limit and self.last_qsize < self.maxsize:
diff --git a/pyspider/processor/processor.py b/pyspider/processor/processor.py
index ae0de1f46..0a919d7dc 100644
--- a/pyspider/processor/processor.py
+++ b/pyspider/processor/processor.py
@@ -6,21 +6,21 @@
 # Created on 2014-02-16 22:59:56
 
 import sys
-import six
 import time
 import logging
 import traceback
-logger = logging.getLogger("processor")
-
 from six.moves import queue as Queue
+import six
 from pyspider.libs import utils
 from pyspider.libs.log import LogFormatter
 from pyspider.libs.utils import pretty_unicode, hide_me
 from pyspider.libs.response import rebuild_response
 from .project_module import ProjectManager, ProjectFinder
 
+logger = logging.getLogger("processor")
+
 
-class ProcessorResult(object):
+class ProcessorResult():
     """The result and logs producted by a callback"""
 
     def __init__(self, result=None, follows=(), messages=(),
@@ -55,11 +55,11 @@ def logstr(self):
                     tb = hide_me(tb, globals())
                     record.exc_info = a, b, tb
                 result.append(pretty_unicode(formater.format(record)))
-                result.append(u'\n')
-        return u''.join(result)
+                result.append('\n')
+        return ''.join(result)
 
 
-class Processor(object):
+class Processor():
     PROCESS_TIME_LIMIT = 30
     EXCEPTION_LIMIT = 3
 
diff --git a/pyspider/processor/project_module.py b/pyspider/processor/project_module.py
index 7adfe708c..ae80c282a 100644
--- a/pyspider/processor/project_module.py
+++ b/pyspider/processor/project_module.py
@@ -6,21 +6,22 @@
 # Created on 2014-02-16 22:24:20
 
 import os
-import six
 import sys
-import imp
+import importlib
 import time
 import weakref
 import logging
 import inspect
 import traceback
 import linecache
+import six
+
 from pyspider.libs import utils
 from pyspider.libs.log import SaveLogHandler, LogFormatter
 logger = logging.getLogger("processor")
 
 
-class ProjectManager(object):
+class ProjectManager():
     """
     load projects from projectdb, update project
     """
@@ -97,11 +98,11 @@ def _need_update(self, project_name, updatetime=None, md5sum=None):
         '''Check if project_name need update'''
         if project_name not in self.projects:
             return True
-        elif md5sum and md5sum != self.projects[project_name]['info'].get('md5sum'):
+        if md5sum and md5sum != self.projects[project_name]['info'].get('md5sum'):
             return True
-        elif updatetime and updatetime > self.projects[project_name]['info'].get('updatetime', 0):
+        if updatetime and updatetime > self.projects[project_name]['info'].get('updatetime', 0):
             return True
-        elif time.time() - self.projects[project_name]['load_time'] > self.RELOAD_PROJECT_INTERVAL:
+        if time.time() - self.projects[project_name]['load_time'] > self.RELOAD_PROJECT_INTERVAL:
             return True
         return False
 
@@ -154,7 +155,7 @@ def get(self, project_name, updatetime=None, md5sum=None):
         return self.projects.get(project_name, None)
 
 
-class ProjectLoader(object):
+class ProjectLoader():
     '''ProjectLoader class for sys.meta_path'''
 
     def __init__(self, project, mod=None):
@@ -165,7 +166,7 @@ def __init__(self, project, mod=None):
 
     def load_module(self, fullname):
         if self.mod is None:
-            self.mod = mod = imp.new_module(fullname)
+            self.mod = mod = importlib.new_module(fullname)
         else:
             mod = self.mod
         mod.__file__ = '<%s>' % self.name
@@ -193,7 +194,7 @@ def get_source(self, fullname):
 
 
 if six.PY2:
-    class ProjectFinder(object):
+    class ProjectFinder():
         '''ProjectFinder class for sys.meta_path'''
 
         def __init__(self, projectdb):
@@ -216,7 +217,7 @@ def find_module(self, fullname, path=None):
                     return ProjectLoader(info)
 
         def load_module(self, fullname):
-            mod = imp.new_module(fullname)
+            mod = importlib.new_module(fullname)
             mod.__file__ = '<projects>'
             mod.__loader__ = self
             mod.__path__ = ['<projects>']
@@ -257,7 +258,7 @@ def find_module(self, fullname, path):
 
     class ProjectsLoader(importlib.abc.InspectLoader):
         def load_module(self, fullname):
-            mod = imp.new_module(fullname)
+            mod = importlib.new_module(fullname)
             mod.__file__ = '<projects>'
             mod.__loader__ = self
             mod.__path__ = ['<projects>']
diff --git a/pyspider/result/result_worker.py b/pyspider/result/result_worker.py
index 16935fa18..43140a2b0 100644
--- a/pyspider/result/result_worker.py
+++ b/pyspider/result/result_worker.py
@@ -12,7 +12,7 @@
 logger = logging.getLogger("result")
 
 
-class ResultWorker(object):
+class ResultWorker():
 
     """
     do with result
@@ -37,9 +37,8 @@ def on_result(self, task, result):
                 url=task['url'],
                 result=result
             )
-        else:
-            logger.warning('result UNKNOW -> %.30r' % result)
-            return
+        logger.warning('result UNKNOW -> %.30r' % result)
+        return
 
     def quit(self):
         self._quit = True
diff --git a/pyspider/run.py b/pyspider/run.py
index 7e3333c5f..26fb73056 100755
--- a/pyspider/run.py
+++ b/pyspider/run.py
@@ -8,12 +8,12 @@
 
 import os
 import sys
-import six
 import copy
 import time
 import shutil
 import logging
 import logging.config
+import six
 
 import click
 import pyspider
diff --git a/pyspider/scheduler/scheduler.py b/pyspider/scheduler/scheduler.py
index 084baff28..e0d8470d9 100644
--- a/pyspider/scheduler/scheduler.py
+++ b/pyspider/scheduler/scheduler.py
@@ -23,7 +23,7 @@
 logger = logging.getLogger('scheduler')
 
 
-class Project(object):
+class Project():
     '''
     project for scheduler
     '''
@@ -66,8 +66,7 @@ def paused(self):
                     logger.error('process not in task, %r', task)
                 if task['track']['process']['ok']:
                     break
-                else:
-                    fail_cnt += 1
+                fail_cnt += 1
                 if fail_cnt >= self.scheduler.FAIL_PAUSE_NUM:
                     break
             if fail_cnt >= self.scheduler.FAIL_PAUSE_NUM:
@@ -90,8 +89,7 @@ def paused(self):
                     # break with enough check cnt
                     cnt = max(cnt, self.scheduler.UNPAUSE_CHECK_NUM)
                     break
-                else:
-                    fail_cnt += 1
+                fail_cnt += 1
             if cnt >= self.scheduler.UNPAUSE_CHECK_NUM:
                 if fail_cnt == cnt:
                     self._paused = True
@@ -137,7 +135,7 @@ def active(self):
         return self.db_status in ('RUNNING', 'DEBUG')
 
 
-class Scheduler(object):
+class Scheduler():
     UPDATE_PROJECT_INTERVAL = 5 * 60
     default_schedule = {
         'priority': 0,
@@ -180,7 +178,7 @@ def __init__(self, taskdb, projectdb, newtask_queue, status_queue,
         self._send_buffer = deque()
         self._quit = False
         self._exceptions = 0
-        self.projects = dict()
+        self.projects = {}
         self._force_update_project = False
         self._last_update_project = 0
         self._last_tick = int(time.time())
@@ -361,7 +359,7 @@ def _check_task_done(self):
                         '%s on_get_info %r', task['project'], task['track'].get('save', {})
                     )
                     continue
-                elif not self.task_verify(task):
+                if not self.task_verify(task):
                     continue
                 self.on_task_status(task)
                 cnt += 1
@@ -476,11 +474,11 @@ def _check_select(self):
 
         taskids = []
         cnt = 0
-        cnt_dict = dict()
+        cnt_dict = {}
         limit = self.LOOP_LIMIT
 
         # dynamic assign select limit for each project, use qsize as weight
-        project_weights, total_weight = dict(), 0
+        project_weights, total_weight = {}, 0
         for project in itervalues(self.projects):  # type:Project
             if not project.active:
                 continue
@@ -714,7 +712,7 @@ def xmlrpc_run(self, port=23333, bind='127.0.0.1', logRequests=False):
         def dump_counter(_time, _type):
             try:
                 return self._cnt[_time].to_dict(_type)
-            except:
+            except Exception:
                 logger.exception('')
         application.register_function(dump_counter, 'counter')
 
@@ -819,8 +817,7 @@ def on_request(self, task):
                                        fields=self.merge_task_fields)
         if oldtask:
             return self.on_old_request(task, oldtask)
-        else:
-            return self.on_new_request(task)
+        return self.on_new_request(task)
 
     def on_new_request(self, task):
         '''Called when a new request is arrived'''
@@ -971,21 +968,20 @@ def on_task_failed(self, task):
             self._cnt['all'].event((project, 'failed'), +1).event((project, 'pending'), -1)
             logger.info('task failed %(project)s:%(taskid)s %(url)s' % task)
             return task
-        else:
-            task['schedule']['retried'] = retried + 1
-            task['schedule']['exetime'] = time.time() + next_exetime
-            task['lastcrawltime'] = time.time()
-            self.update_task(task)
-            self.put_task(task)
+        task['schedule']['retried'] = retried + 1
+        task['schedule']['exetime'] = time.time() + next_exetime
+        task['lastcrawltime'] = time.time()
+        self.update_task(task)
+        self.put_task(task)
 
-            project = task['project']
-            self._cnt['5m'].event((project, 'retry'), +1)
-            self._cnt['1h'].event((project, 'retry'), +1)
-            self._cnt['1d'].event((project, 'retry'), +1)
-            # self._cnt['all'].event((project, 'retry'), +1)
-            logger.info('task retry %d/%d %%(project)s:%%(taskid)s %%(url)s' % (
-                retried, retries), task)
-            return task
+        project = task['project']
+        self._cnt['5m'].event((project, 'retry'), +1)
+        self._cnt['1h'].event((project, 'retry'), +1)
+        self._cnt['1d'].event((project, 'retry'), +1)
+        # self._cnt['all'].event((project, 'retry'), +1)
+        logger.info('task retry %d/%d %%(project)s:%%(taskid)s %%(url)s' % (
+            retried, retries), task)
+        return task
 
     def on_select_task(self, task):
         '''Called when a task is selected to fetch & process'''
@@ -1024,7 +1020,7 @@ def _check_select(self):
         interactive mode of select tasks
         """
         if not self.interactive:
-            return super(OneScheduler, self)._check_select()
+            return super()._check_select()
 
         # waiting for running tasks
         if self.running_task > 0:
@@ -1112,7 +1108,7 @@ def __getattr__(self, name):
     def on_task_status(self, task):
         """Ignore not processing error in interactive mode"""
         if not self.interactive:
-            super(OneScheduler, self).on_task_status(task)
+            super().on_task_status(task)
 
         try:
             procesok = task['track']['process']['ok']
@@ -1187,7 +1183,7 @@ class ThreadBaseScheduler(Scheduler):
     def __init__(self, threads=4, *args, **kwargs):
         self.local = threading.local()
 
-        super(ThreadBaseScheduler, self).__init__(*args, **kwargs)
+        super().__init__(*args, **kwargs)
 
         if isinstance(self.taskdb, SQLiteMixin):
             self.threads = 1
@@ -1263,8 +1259,7 @@ def _run_in_thread(self, method, *args, **kwargs):
                     if block:
                         time.sleep(0.1)
                         continue
-                    else:
-                        queue = self.thread_queues[random.randint(0, len(self.thread_queues)-1)]
+                    queue = self.thread_queues[random.randint(0, len(self.thread_queues)-1)]
                 break
         else:
             queue = self.thread_queues[i % len(self.thread_queues)]
@@ -1296,5 +1291,5 @@ def _load_put_task(self, project, taskid):
         self._run_in_thread(Scheduler._load_put_task, self, project, taskid, _i=i)
 
     def run_once(self):
-        super(ThreadBaseScheduler, self).run_once()
+        super().run_once()
         self._wait_thread()
diff --git a/pyspider/scheduler/task_queue.py b/pyspider/scheduler/task_queue.py
index a6d02e3a5..fd68e6ef3 100644
--- a/pyspider/scheduler/task_queue.py
+++ b/pyspider/scheduler/task_queue.py
@@ -13,9 +13,10 @@
 try:
     from UserDict import DictMixin
 except ImportError:
-    from collections import Mapping as DictMixin
-from .token_bucket import Bucket
+    from collections.abc import Mapping as DictMixin
 from six.moves import queue as Queue
+from .token_bucket import Bucket
+
 
 logger = logging.getLogger('scheduler')
 
@@ -25,7 +26,7 @@
     cmp = lambda x, y: (x > y) - (x < y)
 
 
-class AtomInt(object):
+class AtomInt():
     __value__ = 0
     __mutex__ = threading.RLock()
 
@@ -75,7 +76,7 @@ class PriorityTaskQueue(Queue.Queue):
 
     def _init(self, maxsize):
         self.queue = []
-        self.queue_dict = dict()
+        self.queue_dict = {}
 
     def _qsize(self, len=len):
         return len(self.queue_dict)
@@ -128,7 +129,7 @@ def __delitem__(self, taskid):
         self.queue_dict.pop(taskid).taskid = None
 
 
-class TaskQueue(object):
+class TaskQueue():
     '''
     task queue for scheduler, have a priority queue and a time queue for delayed tasks
     '''
@@ -190,16 +191,16 @@ def _check_processing(self):
     def put(self, taskid, priority=0, exetime=0):
         """
         Put a task into task queue
-        
+
         when use heap sort, if we put tasks(with the same priority and exetime=0) into queue,
         the queue is not a strict FIFO queue, but more like a FILO stack.
-        It is very possible that when there are continuous big flow, the speed of select is 
+        It is very possible that when there are continuous big flow, the speed of select is
         slower than request, resulting in priority-queue accumulation in short time.
-        In this scenario, the tasks more earlier entering the priority-queue will not get 
-        processed until the request flow becomes small. 
-        
-        Thus, we store a global atom self increasing value into task.sequence which represent 
-        the task enqueue sequence. When the comparison of exetime and priority have no 
+        In this scenario, the tasks more earlier entering the priority-queue will not get
+        processed until the request flow becomes small.
+
+        Thus, we store a global atom self increasing value into task.sequence which represent
+        the task enqueue sequence. When the comparison of exetime and priority have no
         difference, we compare task.sequence to ensure that the entire queue is ordered.
         """
         now = time.time()
diff --git a/pyspider/scheduler/token_bucket.py b/pyspider/scheduler/token_bucket.py
index e7bb1b308..9149af0d4 100644
--- a/pyspider/scheduler/token_bucket.py
+++ b/pyspider/scheduler/token_bucket.py
@@ -12,7 +12,7 @@
     import dummy_threading as _threading
 
 
-class Bucket(object):
+class Bucket():
 
     '''
     traffic flow control with token bucket
diff --git a/pyspider/webui/app.py b/pyspider/webui/app.py
index 2261fd6e6..b70ed0a50 100644
--- a/pyspider/webui/app.py
+++ b/pyspider/webui/app.py
@@ -8,7 +8,6 @@
 import os
 import sys
 import logging
-logger = logging.getLogger("webui")
 
 from six import reraise
 from six.moves import builtins
@@ -16,6 +15,8 @@
 from flask import Flask
 from pyspider.fetcher import tornado_fetcher
 
+logger = logging.getLogger("webui")
+
 if os.name == 'nt':
     import mimetypes
     mimetypes.add_type("text/css", ".css", True)
@@ -96,7 +97,7 @@ def quit(self):
     'taskdb': None,
     'projectdb': None,
     'scheduler_rpc': None,
-    'queues': dict(),
+    'queues': {},
     'process_time_limit': 30,
 })
 
@@ -108,10 +109,9 @@ def cdn_url_handler(error, endpoint, kwargs):
         # cdn = app.config.get('cdn', '//cdnjs.cloudflare.com/ajax/libs/')
         cdn = app.config.get('cdn', '//cdnjscn.b0.upaiyun.com/libs/')
         return urljoin(cdn, path)
+    exc_type, exc_value, tb = sys.exc_info()
+    if exc_value is error:
+        reraise(exc_type, exc_value, tb)
     else:
-        exc_type, exc_value, tb = sys.exc_info()
-        if exc_value is error:
-            reraise(exc_type, exc_value, tb)
-        else:
-            raise error
+        raise error
 app.handle_url_build_error = cdn_url_handler
diff --git a/pyspider/webui/debug.py b/pyspider/webui/debug.py
index 6a0694139..8308c5353 100644
--- a/pyspider/webui/debug.py
+++ b/pyspider/webui/debug.py
@@ -74,7 +74,7 @@ def run(project):
     except Exception:
         result = {
             'fetch_result': "",
-            'logs': u'task json error',
+            'logs': 'task json error',
             'follows': [],
             'messages': [],
             'result': None,
@@ -95,7 +95,7 @@ def run(project):
         if not info:
             result = {
                 'fetch_result': "",
-                'logs': u' in wevdav mode, cannot load script',
+                'logs': ' in wevdav mode, cannot load script',
                 'follows': [],
                 'messages': [],
                 'result': None,
@@ -143,7 +143,7 @@ def run(project):
             'time': time.time() - start_time,
         }
         result['fetch_result']['content'] = response.text
-        if (response.headers.get('content-type', '').startswith('image')):
+        if response.headers.get('content-type', '').startswith('image'):
             result['fetch_result']['dataurl'] = dataurl.encode(
                 response.content, response.headers['content-type'])
 
diff --git a/pyspider/webui/index.py b/pyspider/webui/index.py
index 381131d09..d62228a51 100644
--- a/pyspider/webui/index.py
+++ b/pyspider/webui/index.py
@@ -7,14 +7,12 @@
 
 import socket
 
-from six import iteritems, itervalues
-from flask import render_template, request, json
-
+from six import iteritems
 try:
     import flask_login as login
 except ImportError:
     from flask.ext import login
-
+from flask import render_template, request, json
 from .app import app
 
 index_fields = ['name', 'group', 'status', 'comments', 'rate', 'burst', 'updatetime']
@@ -86,9 +84,8 @@ def project_update():
                 app.logger.warning('connect to scheduler rpc error: %r', e)
                 return 'rpc error', 200
         return 'ok', 200
-    else:
-        app.logger.warning("[webui index] projectdb.update() error - res: {}".format(ret))
-        return 'update error', 500
+    app.logger.warning("[webui index] projectdb.update() error - res: {}".format(ret))
+    return 'update error', 500
 
 
 @app.route('/counter')
diff --git a/pyspider/webui/login.py b/pyspider/webui/login.py
index d32d5b73a..6e1eed55d 100644
--- a/pyspider/webui/login.py
+++ b/pyspider/webui/login.py
@@ -6,11 +6,11 @@
 # Created on 2014-12-10 20:36:27
 
 import base64
-from flask import Response
 try:
     import flask_login as login
 except ImportError:
     from flask.ext import login
+from flask import Response
 from .app import app
 
 login_manager = login.LoginManager()
diff --git a/pyspider/webui/result.py b/pyspider/webui/result.py
index 84305bb31..44e0fc2aa 100644
--- a/pyspider/webui/result.py
+++ b/pyspider/webui/result.py
@@ -9,9 +9,10 @@
 
 from flask import render_template, request, json
 from flask import Response
-from .app import app
 from pyspider.libs import result_dump
 
+from .app import app
+
 
 @app.route('/results')
 def result():
@@ -46,9 +47,9 @@ def dump_result(project, _format):
         valid = request.args.get('style', 'rows') == 'full'
         return Response(result_dump.dump_as_json(results, valid),
                         mimetype='application/json')
-    elif _format == 'txt':
+    if _format == 'txt':
         return Response(result_dump.dump_as_txt(results),
                         mimetype='text/plain')
-    elif _format == 'csv':
+    if _format == 'csv':
         return Response(result_dump.dump_as_csv(results),
                         mimetype='text/csv')
diff --git a/pyspider/webui/webdav.py b/pyspider/webui/webdav.py
index 5483dbf19..41aa04bb0 100644
--- a/pyspider/webui/webdav.py
+++ b/pyspider/webui/webdav.py
@@ -32,8 +32,7 @@ def check_user(environ):
     if username == app.config['webui_username'] \
             and password == app.config['webui_password']:
         return True
-    else:
-        return False
+    return False
 
 
 class ContentIO(BytesIO):
@@ -44,7 +43,7 @@ def close(self):
 
 class ScriptResource(DAVNonCollection):
     def __init__(self, path, environ, app, project=None):
-        super(ScriptResource, self).__init__(path, environ)
+        super().__init__(path, environ)
 
         self.app = app
         self.new_project = False
@@ -102,14 +101,14 @@ def getContent(self):
     def beginWrite(self, contentType=None):
         if self.readonly:
             self.app.logger.error('webdav.beginWrite readonly')
-            return super(ScriptResource, self).beginWrite(contentType)
+            return super().beginWrite(contentType)
         self.writebuffer = ContentIO()
         return self.writebuffer
 
     def endWrite(self, withErrors):
         if withErrors:
             self.app.logger.error('webdav.endWrite error: %r', withErrors)
-            return super(ScriptResource, self).endWrite(withErrors)
+            return super().endWrite(withErrors)
         if not self.writebuffer:
             return
         projectdb = self.app.config['projectdb']
@@ -126,13 +125,12 @@ def endWrite(self, withErrors):
             self.project.update(info)
             self.new_project = False
             return projectdb.insert(self.project_name, self.project)
-        else:
-            return projectdb.update(self.project_name, info)
+        return projectdb.update(self.project_name, info)
 
 
 class RootCollection(DAVCollection):
     def __init__(self, path, environ, app):
-        super(RootCollection, self).__init__(path, environ)
+        super().__init__(path, environ)
         self.app = app
         self.projectdb = self.app.config['projectdb']
 
@@ -164,7 +162,7 @@ def getMemberNames(self):
 
 class ScriptProvider(DAVProvider):
     def __init__(self, app):
-        super(ScriptProvider, self).__init__()
+        super().__init__()
         self.app = app
 
     def __repr__(self):
@@ -175,11 +173,10 @@ def getResourceInst(self, path, environ):
         if path in ('/', '.', ''):
             path = '/'
             return RootCollection(path, environ, self.app)
-        else:
-            return ScriptResource(path, environ, self.app)
+        return ScriptResource(path, environ, self.app)
 
 
-class NeedAuthController(object):
+class NeedAuthController():
     def __init__(self, app):
         self.app = app
 
diff --git a/setup.py b/setup.py
index 2512f4708..e205f5ca9 100644
--- a/setup.py
+++ b/setup.py
@@ -6,16 +6,17 @@
 # Created on 2014-11-24 22:27:45
 
 
-import sys
-from setuptools import setup, find_packages
 from codecs import open
 from os import path
+from setuptools import setup, find_packages
+
+import pyspider
 
 here = path.abspath(path.dirname(__file__))
 with open(path.join(here, 'README.md'), encoding='utf-8') as f:
     long_description = f.read()
 
-import pyspider
+
 
 install_requires = [
     'Flask==0.10',
diff --git a/tests/data_handler.py b/tests/data_handler.py
index 3f77235c7..1f3fed04f 100644
--- a/tests/data_handler.py
+++ b/tests/data_handler.py
@@ -9,7 +9,7 @@
 import time
 from pyspider.libs.base_handler import BaseHandler, catch_status_code_error, every
 
-class IgnoreHandler(object):
+class IgnoreHandler():
     pass
 
 class TestHandler(BaseHandler):
@@ -42,7 +42,7 @@ def raise_exception(self):
         raise Exception('exception')
 
     def add_task(self, response):
-        self.crawl('http://www.google.com', callback='echo', params={'wd': u'中文'})
+        self.crawl('http://www.google.com', callback='echo', params={'wd': '中文'})
         self.send_message('some_project', {'some': 'message'})
 
     @every
@@ -59,4 +59,3 @@ def generator(self, response):
 
     def sleep(self, response):
         time.sleep(response.save)
-
diff --git a/tests/test_base_handler.py b/tests/test_base_handler.py
index 317e12a60..65fd06301 100644
--- a/tests/test_base_handler.py
+++ b/tests/test_base_handler.py
@@ -43,7 +43,7 @@ def test_task_join_crawl_config(self):
                 'c': 'd',           # should add header c
             }
         }
-        
+
         ret = BaseHandler.task_join_crawl_config(task, crawl_config)
         self.assertDictEqual(ret, {
             'taskid': 'taskid',
@@ -67,4 +67,4 @@ def test_task_join_crawl_config(self):
                 'callback': 'callback',
                 'save': [1, 2, 3],
             },
-        });
+        })
diff --git a/tests/test_bench.py b/tests/test_bench.py
index 9b584700f..08299691c 100644
--- a/tests/test_bench.py
+++ b/tests/test_bench.py
@@ -6,9 +6,6 @@
 # Created on 2014-12-10 01:34:09
 
 import os
-import sys
-import time
-import click
 import shutil
 import inspect
 import unittest
diff --git a/tests/test_counter.py b/tests/test_counter.py
index 03ceb4203..4d0f697e2 100644
--- a/tests/test_counter.py
+++ b/tests/test_counter.py
@@ -5,7 +5,6 @@
 #         http://binux.me
 # Created on 2015-04-05 00:05:58
 
-import sys
 import time
 import unittest
 
@@ -44,7 +43,7 @@ def test_020_delete(self):
         c.event(('a', 'b'), 1)
         c.event(('a', 'c'), 1)
         c.event(('b', 'c'), 1)
-        
+
         self.assertIsNotNone(c['a'])
         self.assertIsNotNone(c['b'])
 
diff --git a/tests/test_database.py b/tests/test_database.py
index f9d563a3b..3504b9fa7 100644
--- a/tests/test_database.py
+++ b/tests/test_database.py
@@ -8,7 +8,6 @@
 from __future__ import unicode_literals, division
 
 import os
-import six
 import time
 import unittest
 
@@ -16,7 +15,7 @@
 from pyspider.database.base.taskdb import TaskDB
 
 
-class TaskDBCase(object):
+class TaskDBCase():
     sample_task = {
         'taskid': 'taskid',
         'project': 'project',
@@ -58,7 +57,7 @@ class TaskDBCase(object):
                 'time': 10,
                 'follows': 3,
                 'outputs': 5,
-                'exception': u"中文",
+                'exception': "中文",
             },
         },
         'lastcrawltime': time.time(),
@@ -66,7 +65,7 @@ class TaskDBCase(object):
     }
 
     @classmethod
-    def setUpClass(self):
+    def setUpClass(cls):
         raise NotImplementedError
 
     # this test not works for mongodb
@@ -155,7 +154,7 @@ def test_z20_update_projects(self):
         self.taskdb.UPDATE_PROJECTS_TIME = saved
 
 
-class ProjectDBCase(object):
+class ProjectDBCase():
     sample_project = {
         'name': 'name',
         'script': 'import time\nprint(time.time(), "!@#$%^&*()\';:<>?/|")',
@@ -170,7 +169,7 @@ def setUpClass(self):
 
     def test_10_insert(self):
         self.projectdb.insert('abc', self.sample_project)
-        self.projectdb.insert(u'name中文', self.sample_project)
+        self.projectdb.insert('name中文', self.sample_project)
         project = self.projectdb.get('abc')
         self.assertIsNotNone(project)
 
@@ -183,7 +182,7 @@ def test_20_get_all(self):
         for key in ('name', 'group', 'status', 'script', 'comments', 'rate', 'burst', 'updatetime'):
             self.assertIn(key, project)
 
-        self.assertEqual(project['name'], u'abc')
+        self.assertEqual(project['name'], 'abc')
         self.assertEqual(project['status'], self.sample_project['status'])
         self.assertEqual(project['script'], self.sample_project['script'])
         self.assertEqual(project['rate'], self.sample_project['rate'])
@@ -232,20 +231,20 @@ def test_50_get(self):
         self.assertEqual(project['name'], 'abc')
         self.assertEqual(project['status'], 'RUNNING')
 
-        project = self.projectdb.get(u'name中文', ['group', 'status', 'name'])
-        self.assertEqual(project['name'], u'name中文')
+        project = self.projectdb.get('name中文', ['group', 'status', 'name'])
+        self.assertEqual(project['name'], 'name中文')
         self.assertIn('status', project)
         self.assertNotIn('gourp', project)
 
     def test_z10_drop(self):
-        self.projectdb.insert(u'drop_project2', self.sample_project)
-        self.projectdb.insert(u'drop_project3', self.sample_project)
+        self.projectdb.insert('drop_project2', self.sample_project)
+        self.projectdb.insert('drop_project3', self.sample_project)
         self.projectdb.drop('drop_project3')
         self.assertIsNotNone(self.projectdb.get('drop_project2'))
         self.assertIsNone(self.projectdb.get('drop_project3'))
 
 
-class ResultDBCase(object):
+class ResultDBCase():
 
     @classmethod
     def setUpClass(self):
diff --git a/tests/test_fetcher.py b/tests/test_fetcher.py
index 02ace999c..2d2ba6733 100644
--- a/tests/test_fetcher.py
+++ b/tests/test_fetcher.py
@@ -10,22 +10,25 @@
 import copy
 import time
 import socket
-import umsgpack
 import subprocess
 import unittest
 
 import logging
 import logging.config
+import umsgpack
+
+from pyspider.libs import utils
+from pyspider.libs.multiprocessing_queue import Queue
+from pyspider.libs.response import rebuild_response
+from pyspider.fetcher.tornado_fetcher import Fetcher
+
 logging.config.fileConfig("pyspider/logging.conf")
 
 try:
     from six.moves import xmlrpc_client
 except ImportError:
     import xmlrpclib as xmlrpc_client
-from pyspider.libs import utils
-from pyspider.libs.multiprocessing_queue import Queue
-from pyspider.libs.response import rebuild_response
-from pyspider.fetcher.tornado_fetcher import Fetcher
+
 
 
 class TestFetcher(unittest.TestCase):
@@ -173,7 +176,7 @@ def test_50_base64_data(self):
 
         self.assertEqual(response.status_code, 200, response.error)
         self.assertIsNotNone(response.json, response.content)
-        self.assertIn(u'中文', response.json['form'], response.json)
+        self.assertIn('中文', response.json['form'], response.json)
 
     def test_55_base64_data(self):
         request = copy.deepcopy(self.sample_task_http)
@@ -459,7 +462,7 @@ def setUpClass(self):
                                               '--password=123456', '--port=14830',
                                               '--debug'], close_fds=True)
         self.proxy = socket.gethostbyname(socket.gethostname()) + ':14830'
-        
+
     @classmethod
     def tearDownClass(self):
         self.rpc("close")()
diff --git a/tests/test_fetcher_processor.py b/tests/test_fetcher_processor.py
index 44cf2c1d3..5956c1bb5 100644
--- a/tests/test_fetcher_processor.py
+++ b/tests/test_fetcher_processor.py
@@ -7,15 +7,16 @@
 
 import os
 import time
-import httpbin
 import subprocess
 import unittest
+import httpbin
+
+from six.moves.queue import Queue
 
 from pyspider.database.local.projectdb import ProjectDB
 from pyspider.fetcher import Fetcher
 from pyspider.processor import Processor
 from pyspider.libs import utils, dataurl
-from six.moves.queue import Queue
 from tests.data_fetcher_processor_handler import Handler
 
 
@@ -154,22 +155,22 @@ def test_40_method(self):
     def test_50_params(self):
         status, newtasks, result = self.crawl(self.httpbin + '/get', params={
             'roy': 'binux',
-            u'中文': '.',
+            '中文': '.',
         }, callback=self.json)
 
         self.assertStatusOk(status)
         self.assertFalse(newtasks)
-        self.assertEqual(result['args'], {'roy': 'binux', u'中文': '.'})
+        self.assertEqual(result['args'], {'roy': 'binux', '中文': '.'})
 
     def test_60_data(self):
         status, newtasks, result = self.crawl(self.httpbin + '/post', data={
             'roy': 'binux',
-            u'中文': '.',
+            '中文': '.',
         }, callback=self.json)
 
         self.assertStatusOk(status)
         self.assertFalse(newtasks)
-        self.assertEqual(result['form'], {'roy': 'binux', u'中文': '.'})
+        self.assertEqual(result['form'], {'roy': 'binux', '中文': '.'})
 
     def test_70_redirect(self):
         status, newtasks, result = self.crawl(self.httpbin + '/redirect-to?url=/get', callback=self.json)
@@ -189,7 +190,7 @@ def test_80_redirect_too_many(self):
 
     def test_90_files(self):
         status, newtasks, result = self.crawl(self.httpbin + '/put', method='PUT',
-                                              files={os.path.basename(__file__): open(__file__).read()},
+                                              files={os.path.basename(__file__): open(__file__, encoding='utf-8').read()},
                                               callback=self.json)
 
         self.assertStatusOk(status)
@@ -198,7 +199,7 @@ def test_90_files(self):
 
     def test_a100_files_with_data(self):
         status, newtasks, result = self.crawl(self.httpbin + '/put', method='PUT',
-                                              files={os.path.basename(__file__): open(__file__).read()},
+                                              files={os.path.basename(__file__): open(__file__, encoding='utf-8').read()},
                                               data={
                                                   'roy': 'binux',
                                                   # '中文': '.', # FIXME: not work
@@ -293,11 +294,11 @@ def test_a170_last_modified(self):
 
     def test_a180_save(self):
         status, newtasks, result = self.crawl(callback=self.get_save,
-                                              save={'roy': 'binux', u'中文': 'value'})
+                                              save={'roy': 'binux', '中文': 'value'})
 
         self.assertStatusOk(status)
         self.assertFalse(newtasks)
-        self.assertEqual(result, {'roy': 'binux', u'中文': 'value'})
+        self.assertEqual(result, {'roy': 'binux', '中文': 'value'})
 
     def test_a190_taskid(self):
         status, newtasks, result = self.crawl(callback=self.get_save,
@@ -434,7 +435,7 @@ def test_zzz_etag_not_working(self):
         self.assertTrue(result)
 
     def test_zzz_unexpected_crawl_argument(self):
-        with self.assertRaisesRegexp(TypeError, "unexpected keyword argument"):
+        with self.assertRaisesRegex(TypeError, "unexpected keyword argument"):
             self.crawl(self.httpbin + '/cache', cookie={}, callback=self.json)
 
     def test_zzz_curl_get(self):
@@ -465,18 +466,18 @@ def test_zzz_curl_put(self):
         self.assertIn('fileUpload1', result['files'], result)
 
     def test_zzz_curl_no_url(self):
-        with self.assertRaisesRegexp(TypeError, 'no URL'):
+        with self.assertRaisesRegex(TypeError, 'no URL'):
             status, newtasks, result = self.crawl(
                 '''curl -X PUT -H 'Origin: chrome-extension://hgmloofddffdnphfgcellkdfbfbjeloo' --compressed''',
                 callback=self.json)
 
     def test_zzz_curl_bad_option(self):
-        with self.assertRaisesRegexp(TypeError, 'Unknow curl option'):
+        with self.assertRaisesRegex(TypeError, 'Unknow curl option'):
             status, newtasks, result = self.crawl(
                 '''curl '%s/put' -X PUT -H 'Origin: chrome-extension://hgmloofddffdnphfgcellkdfbfbjeloo' -v''' % self.httpbin,
                 callback=self.json)
 
-        with self.assertRaisesRegexp(TypeError, 'Unknow curl option'):
+        with self.assertRaisesRegex(TypeError, 'Unknow curl option'):
             status, newtasks, result = self.crawl(
                 '''curl '%s/put' -X PUT -v -H 'Origin: chrome-extension://hgmloofddffdnphfgcellkdfbfbjeloo' ''' % self.httpbin,
                 callback=self.json)
@@ -490,4 +491,4 @@ def test_zzz_connect_timeout(self):
         start_time = time.time()
         status, newtasks, result = self.crawl('http://240.0.0.1/', connect_timeout=5, callback=self.catch_http_error)
         end_time = time.time()
-        self.assertTrue(5 <= end_time - start_time <= 6)
\ No newline at end of file
+        self.assertTrue(5 <= end_time - start_time <= 6)
diff --git a/tests/test_message_queue.py b/tests/test_message_queue.py
index d5e19559b..03bd8cfc1 100644
--- a/tests/test_message_queue.py
+++ b/tests/test_message_queue.py
@@ -6,15 +6,15 @@
 # Created on 2014-10-07 10:33:38
 
 import os
-import six
 import time
 import unittest
+import six
 
-from pyspider.libs import utils
 from six.moves import queue as Queue
+from pyspider.libs import utils
 
 
-class TestMessageQueue(object):
+class TestMessageQueue():
 
     @classmethod
     def setUpClass(self):
@@ -41,9 +41,9 @@ def test_30_full(self):
         self.assertEqual(self.q1.qsize(), 0)
         self.assertEqual(self.q2.qsize(), 0)
         for i in range(2):
-            self.q1.put_nowait('TEST_DATA%d' % i)
+            self.q1.put_nowait(f'TEST_DATA{i}')
         for i in range(3):
-            self.q2.put('TEST_DATA%d' % i)
+            self.q2.put(f'TEST_DATA{i}')
 
         with self.assertRaises(Queue.Full):
             self.q1.put('TEST_DATA6', timeout=0.01)
@@ -101,9 +101,9 @@ def test_30_full(self):
         self.assertEqual(self.q1.qsize(), 0)
         self.assertEqual(self.q2.qsize(), 0)
         for i in range(2):
-            self.q1.put_nowait('TEST_DATA%d' % i)
+            self.q1.put_nowait(f'TEST_DATA{i}')
         for i in range(3):
-            self.q2.put('TEST_DATA%d' % i)
+            self.q2.put(f'TEST_DATA{i}')
 
         print(self.q1.__dict__)
         print(self.q1.qsize())
diff --git a/tests/test_processor.py b/tests/test_processor.py
index 1a07960cb..db4364429 100644
--- a/tests/test_processor.py
+++ b/tests/test_processor.py
@@ -6,16 +6,15 @@
 # Created on 2014-02-22 14:00:05
 
 import os
-import six
-import copy
 import time
 import unittest
 import logging.config
-logging.config.fileConfig("pyspider/logging.conf")
 
 from pyspider.libs import utils
 from pyspider.processor.project_module import ProjectManager
 
+logging.config.fileConfig("pyspider/logging.conf")
+
 
 class TestProjectModule(unittest.TestCase):
 
@@ -65,7 +64,7 @@ def fetch_result(self):
 
     def setUp(self):
         self.project = "test.project"
-        self.script = open(os.path.join(os.path.dirname(__file__), 'data_handler.py')).read()
+        self.script = open(os.path.join(os.path.dirname(__file__), 'data_handler.py'), encoding='utf-8').read()
         self.env = {
             'test': True,
         }
diff --git a/tests/test_response.py b/tests/test_response.py
index 4b9bbf094..cd47b6c4f 100644
--- a/tests/test_response.py
+++ b/tests/test_response.py
@@ -6,20 +6,23 @@
 # Created on 2015-01-18 11:10:27
 
 
-import os
 import copy
 import time
-import httpbin
 import unittest
 
 import logging
 import logging.config
-logging.config.fileConfig("pyspider/logging.conf")
+
+import httpbin
 
 from pyspider.libs import utils
 from pyspider.libs.response import rebuild_response
 from pyspider.fetcher.tornado_fetcher import Fetcher
 
+logging.config.fileConfig("pyspider/logging.conf")
+
+
+
 class TestResponse(unittest.TestCase):
     sample_task_http = {
         'taskid': 'taskid',
diff --git a/tests/test_result_dump.py b/tests/test_result_dump.py
index 0d6e933e7..00ff9defc 100644
--- a/tests/test_result_dump.py
+++ b/tests/test_result_dump.py
@@ -7,7 +7,6 @@
 
 from __future__ import unicode_literals, division
 
-import six
 import csv
 import time
 import json
@@ -25,7 +24,7 @@
 
 results2 = results1 + [
     {'taskid': 'taskid1', 'url': 'http://example.org/url1', 'pdatetime': time.time(),
-     'result': [1, 2, '中文', u'中文'] },
+     'result': [1, 2, '中文', '中文'] },
 ]
 
 results_error = results2 + [
diff --git a/tests/test_result_worker.py b/tests/test_result_worker.py
index 9933cfed8..e80670080 100644
--- a/tests/test_result_worker.py
+++ b/tests/test_result_worker.py
@@ -9,7 +9,6 @@
 import time
 import unittest
 import logging.config
-logging.config.fileConfig("pyspider/logging.conf")
 
 import shutil
 from pyspider.database.sqlite import resultdb
@@ -17,6 +16,9 @@
 from pyspider.libs.multiprocessing_queue import Queue
 from pyspider.libs.utils import run_in_thread
 
+logging.config.fileConfig("pyspider/logging.conf")
+
+
 
 class TestProcessor(unittest.TestCase):
     resultdb_path = './data/tests/result.db'
diff --git a/tests/test_run.py b/tests/test_run.py
index 490844ee4..81075a9e1 100644
--- a/tests/test_run.py
+++ b/tests/test_run.py
@@ -8,15 +8,14 @@
 from __future__ import print_function
 
 import os
-import sys
-import six
 import time
 import json
 import signal
 import shutil
 import inspect
-import requests
 import unittest
+import requests
+
 
 from pyspider import run
 from pyspider.libs import utils
@@ -29,7 +28,6 @@ def setUpClass(self):
         shutil.rmtree('./data/tests', ignore_errors=True)
         os.makedirs('./data/tests')
 
-        import tests.data_test_webpage
         import httpbin
         self.httpbin_thread = utils.run_in_subprocess(httpbin.app.run, port=14887, passthrough_errors=False)
         self.httpbin = 'http://127.0.0.1:14887'
@@ -59,7 +57,7 @@ def test_10_cli(self):
         self.assertEqual(len(ctx.obj.instances), 0)
 
     def test_20_cli_config(self):
-        with open('./data/tests/config.json', 'w') as fp:
+        with open('./data/tests/config.json', 'w', encoding='utf-8') as fp:
             json.dump({
                 'debug': True,
                 'taskdb': 'mysql+taskdb://localhost:23456/taskdb',
@@ -263,7 +261,7 @@ def test_a100_all(self):
             rv = requests.get('http://localhost:5000/results?project=data_sample_handler')
             self.assertIn('<th>url</th>', rv.text)
             self.assertIn('class=url', rv.text)
-        except:
+        except Exception:
             raise
         finally:
             time.sleep(1)
@@ -312,18 +310,18 @@ def wait_text(timeout=1):
             text = wait_text()
             self.assertIn('task done data_sample_handler:on_start', text)
 
-            os.write(fd, utils.utf8('crawl("%s/pyspider/test.html")\n' % self.httpbin))
+            os.write(fd, utils.utf8(f'crawl("{self.httpbin}/pyspider/test.html")\n'))
             text = wait_text()
             self.assertIn('/robots.txt', text)
 
-            os.write(fd, utils.utf8('crawl("%s/links/10/0")\n' % self.httpbin))
+            os.write(fd, utils.utf8(f'crawl("{self.httpbin}/links/10/0")\n'))
             text = wait_text()
             if '"title": "Links"' not in text:
-                os.write(fd, utils.utf8('crawl("%s/links/10/1")\n' % self.httpbin))
+                os.write(fd, utils.utf8(f'crawl("{self.httpbin}/links/10/1")\n'))
                 text = wait_text()
                 self.assertIn('"title": "Links"', text)
 
-            os.write(fd, utils.utf8('crawl("%s/404")\n' % self.httpbin))
+            os.write(fd, utils.utf8(f'crawl("{self.httpbin}/404")\n'))
             text = wait_text()
             self.assertIn('task retry', text)
 
@@ -379,4 +377,3 @@ def test_10_send_message(self):
             if task['url'] == 'data:,on_message':
                 break
         self.assertEqual(task['process']['callback'], '_on_message')
-
diff --git a/tests/test_scheduler.py b/tests/test_scheduler.py
index 66ac000eb..41a86ff87 100644
--- a/tests/test_scheduler.py
+++ b/tests/test_scheduler.py
@@ -11,11 +11,13 @@
 import unittest
 import logging
 import logging.config
-logging.config.fileConfig("pyspider/logging.conf")
 
 from pyspider.scheduler.task_queue import TaskQueue
 from pyspider.libs import utils
 
+logging.config.fileConfig("pyspider/logging.conf")
+
+
 
 class TestTaskQueue(unittest.TestCase):
 
@@ -129,7 +131,7 @@ def get_resultdb():
         self.newtask_queue = Queue(10)
         self.status_queue = Queue(10)
         self.scheduler2fetcher = Queue(10)
-        self.rpc = xmlrpc_client.ServerProxy('http://localhost:%d' % self.scheduler_xmlrpc_port)
+        self.rpc = xmlrpc_client.ServerProxy(f'http://localhost:{self.scheduler_xmlrpc_port}')
 
         def run_scheduler():
             scheduler = Scheduler(taskdb=get_taskdb(), projectdb=get_projectdb(),
@@ -329,7 +331,7 @@ def test_60_taskdone_failed_retry(self):
                 },
             }
         })  # task retry 0/3 test_project:taskid url
-        from six.moves import queue as Queue
+        #from six.moves import queue as Queue
         # with self.assertRaises(Queue.Empty):
             # task = self.scheduler2fetcher.get(timeout=4)
         task = self.scheduler2fetcher.get(timeout=5)  # select test_project:taskid url
@@ -702,7 +704,7 @@ def test_x10_inqueue_limit(self):
         pre_size = self.rpc.size()
         for i in range(20):
             self.newtask_queue.put({
-                'taskid': 'taskid%d' % i,
+                'taskid': f'taskid{i}',
                 'project': 'test_inqueue_project',
                 'url': 'url',
                 'schedule': {
diff --git a/tests/test_task_queue.py b/tests/test_task_queue.py
index a84fc98e6..193314cbe 100644
--- a/tests/test_task_queue.py
+++ b/tests/test_task_queue.py
@@ -18,8 +18,8 @@ class TestTaskQueue(unittest.TestCase):
     def test_task_queue_in_time_order(self):
         tq = TaskQueue(rate=300, burst=1000)
 
-        queues = dict()
-        tasks = dict()
+        queues = {}
+        tasks = {}
 
         for i in range(0, 100):
             it = InQueueTask(str(i), priority=int(i // 10), exetime=0)
@@ -81,8 +81,8 @@ def test_time_queue(self):
         self.assertEqual(tq.processing.qsize(), 0)
         self.assertEqual(tq.time_queue.qsize(), 0)
 
-        queues = dict()
-        tasks = dict()
+        queues = {}
+        tasks = {}
         for i in range(0, 20):
             priority = int(i // 10)
             it = InQueueTask(str(i), priority=priority, exetime=time.time() + (i + 1) * interval)
diff --git a/tests/test_utils.py b/tests/test_utils.py
index b64a3baad..e250e8779 100644
--- a/tests/test_utils.py
+++ b/tests/test_utils.py
@@ -5,7 +5,6 @@
 #         http://binux.me
 # Created on 2015-01-18 16:53:49
 
-import sys
 import time
 import unittest
 
diff --git a/tests/test_webdav.py b/tests/test_webdav.py
index ccb40a6e6..d8330a6a5 100644
--- a/tests/test_webdav.py
+++ b/tests/test_webdav.py
@@ -7,11 +7,9 @@
 
 import os
 import sys
-import six
 import time
 import shutil
 import inspect
-import unittest
 
 from six import BytesIO
 from pyspider import run
diff --git a/tests/test_webui.py b/tests/test_webui.py
index 1e232cee8..bceae1bf2 100644
--- a/tests/test_webui.py
+++ b/tests/test_webui.py
@@ -329,7 +329,7 @@ def test_a22_active_tasks(self):
                 self.assertIn('ok', task['track']['process'])
                 self.assertIn('time', task['track']['process'])
         self.assertTrue(track)
-                    
+
 
     def test_a24_task(self):
         rv = self.app.get(self.task_url)
diff --git a/tests/test_xmlrpc.py b/tests/test_xmlrpc.py
index 736d94e8d..52d83173a 100644
--- a/tests/test_xmlrpc.py
+++ b/tests/test_xmlrpc.py
@@ -24,16 +24,16 @@ class TestXMLRPCServer(unittest.TestCase):
     @classmethod
     def setUpClass(self):
         from pyspider.libs import wsgi_xmlrpc
-        
+
         def test_1():
             return 'test_1'
-            
-        class Test2(object):
+
+        class Test2():
             def test_3(self, obj):
                 return obj
-                
+
         test = Test2()
-        
+
         application = wsgi_xmlrpc.WSGIXMLRPCApplication()
         application.register_instance(Test2())
         application.register_function(test_1)
@@ -48,11 +48,11 @@ def test_3(self, obj):
     def tearDownClass(self):
         self.io_loop.add_callback(self.io_loop.stop)
         self.thread.join()
-    
+
     def test_xmlrpc_server(self, uri='http://127.0.0.1:3423'):
         from six.moves.xmlrpc_client import ServerProxy
-        
+
         client = ServerProxy(uri)
-        
+
         assert client.test_1() == 'test_1'
         assert client.test_3({'asdf':4}) == {'asdf':4}
diff --git a/tools/migrate.py b/tools/migrate.py
index f092daa6b..567b69965 100755
--- a/tools/migrate.py
+++ b/tools/migrate.py
@@ -5,14 +5,16 @@
 #         http://binux.me
 # Created on 2015-09-30 23:22:46
 
-import click
 import logging
+from multiprocessing.pool import ThreadPool as Pool
+import click
+
 from pyspider.database.base.projectdb import ProjectDB
 from pyspider.database.base.taskdb import TaskDB
 from pyspider.database.base.resultdb import ResultDB
 from pyspider.database import connect_database
 from pyspider.libs.utils import unicode_obj
-from multiprocessing.pool import ThreadPool as Pool
+
 
 logging.getLogger().setLevel(logging.INFO)