DM-22234: Remove python 2 support

python/lsst/daf/persistence/__init__.py

@@ -22,7 +22,6 @@
 
 """Python interface to lsst::daf::persistence classes
 """
-from __future__ import absolute_import
 
 StorageList = list
 
@@ -54,4 +53,3 @@
 from .butlerFactory import *
 from .butlerHelpers import *
 from .version import *
-

python/lsst/daf/persistence/access.py

@@ -20,7 +20,6 @@
 # the GNU General Public License along with this program.  If not,
 # see <http://www.lsstcorp.org/LegalNotices/>.
 #
-from builtins import object, super
 
 from lsst.daf.persistence import Policy
 
@@ -34,7 +33,7 @@ def __init__(self, cls, storageCfg):
         super().__init__({'storageCfg': storageCfg, 'cls': cls})
 
 
-class Access(object):
+class Access:
     """Implements an butler framework interface for Transport, Storage, and Registry
 
     .. warning::

python/lsst/daf/persistence/butler.py

@@ -25,10 +25,6 @@
 # -*- python -*-
 
 """This module defines the Butler class."""
-from builtins import str, super
-from past.builtins import basestring
-from builtins import object
-
 import copy
 import inspect
 
@@ -62,7 +58,7 @@ def __init__(self, cls, repoCfg):
         super().__init__({'repoCfg': repoCfg, 'cls': cls})
 
 
-class RepoData(object):
+class RepoData:
     """Container object for repository data used by Butler
 
     Parameters
@@ -240,7 +236,7 @@ def addTags(self, tags):
         self.tags = self.tags.union(tags)
 
 
-class RepoDataContainer(object):
+class RepoDataContainer:
     """Container object for RepoData instances owned by a Butler instance.
 
         Parameters
@@ -322,7 +318,7 @@ def addToList(repoData, lst):
         self._outputs = [repoData.repoData for repoData in outputs]
 
 
-class Butler(object):
+class Butler:
     """Butler provides a generic mechanism for persisting and retrieving data using mappers.
 
     A Butler manages a collection of datasets known as a repository. Each dataset has a type representing its
@@ -625,7 +621,7 @@ def _processInputArguments(self, root=None, mapper=None, inputs=None, outputs=No
                 raise RuntimeError("The mode of an output should be writable.")
         # check for class instances in args.mapper (not allowed)
         for args in inputs + outputs:
-            if (args.mapper and not isinstance(args.mapper, basestring) and
+            if (args.mapper and not isinstance(args.mapper, str) and
                not inspect.isclass(args.mapper)):
                 self.log.warn(preinitedMapperWarning)
         # if the output is readable, there must be only one output:
@@ -1015,7 +1011,7 @@ def _convertV1Args(self, root, mapper, mapperArgs):
         tuple
             (inputs, outputs) - values to be used for inputs and outputs in Butler.__init__
         """
-        if (mapper and not isinstance(mapper, basestring) and
+        if (mapper and not isinstance(mapper, str) and
            not inspect.isclass(mapper)):
             self.log.warn(preinitedMapperWarning)
         inputs = None
@@ -1067,7 +1063,7 @@ def _getDefaultMapper(self):
                 # * a string, import it.
                 # * a class instance, get its class type
                 # * a class, do nothing; use it
-                if isinstance(mapper, basestring):
+                if isinstance(mapper, str):
                     mapper = doImport(mapper)
                 elif not inspect.isclass(mapper):
                     mapper = mapper.__class__
@@ -1348,7 +1344,7 @@ def _locate(self, datasetType, dataId, write):
     def _getBypassFunc(location, dataId):
         pythonType = location.getPythonType()
         if pythonType is not None:
-            if isinstance(pythonType, basestring):
+            if isinstance(pythonType, str):
                 pythonType = doImport(pythonType)
         bypassFunc = getattr(location.mapper, "bypass_" + location.datasetType)
         return lambda: bypassFunc(location.datasetType, pythonType, location, dataId)

python/lsst/daf/persistence/butlerExceptions.py

@@ -19,7 +19,6 @@
 # the GNU General Public License along with this program.  If not,
 # see <http://www.lsstcorp.org/LegalNotices/>.
 #
-from builtins import str, super
 
 
 class NoMapperException(Exception):

python/lsst/daf/persistence/butlerFactory.py

@@ -25,12 +25,11 @@
 # -*- python -*-
 
 """This module defines the ButlerFactory class."""
-from builtins import object
 
 from lsst.daf.persistence import Butler
 
 
-class ButlerFactory(object):
+class ButlerFactory:
     """ButlerFactory creates data Butlers containing data mappers.  Use of it
     is deprecated in favor of the direct Butler constructor.
 

python/lsst/daf/persistence/butlerLocation.py

@@ -28,13 +28,12 @@
 import lsst.daf.base as dafBase
 
 import os
-from past.builtins import basestring
 import yaml
 
 from . import iterify, doImport
 
 
-class ButlerComposite(object):
+class ButlerComposite:
     """Initializer
 
     Parameters
@@ -101,9 +100,9 @@ def __repr__(self):
              self.repository)
 
     def __init__(self, assembler, disassembler, python, dataId, mapper):
-        self.assembler = doImport(assembler) if isinstance(assembler, basestring) else assembler
-        self.disassembler = doImport(disassembler) if isinstance(disassembler, basestring) else disassembler
-        self.python = doImport(python) if isinstance(python, basestring) else python
+        self.assembler = doImport(assembler) if isinstance(assembler, str) else assembler
+        self.disassembler = doImport(disassembler) if isinstance(disassembler, str) else disassembler
+        self.python = doImport(python) if isinstance(python, str) else python
         self.dataId = dataId
         self.mapper = mapper
         self.componentInfo = {}
@@ -209,8 +208,7 @@ def __repr__(self):
 
     def __init__(self, pythonType, cppType, storageName, locationList, dataId, mapper, storage,
                  usedDataId=None, datasetType=None, additionalData=None):
-        # pythonType is sometimes unicode with Python 2 and pybind11; this breaks the interpreter
-        self.pythonType = str(pythonType) if isinstance(pythonType, basestring) else pythonType
+        self.pythonType = pythonType
         self.cppType = cppType
         self.storageName = storageName
         self.mapper = mapper

python/lsst/daf/persistence/butlerSubset.py

@@ -26,14 +26,11 @@
 
 """This module defines the ButlerSubset class and the ButlerDataRefs contained
 within it as well as an iterator over the subset."""
-from builtins import next
-from builtins import range
-from builtins import object
 
 from . import DataId
 
 
-class ButlerSubset(object):
+class ButlerSubset:
 
     """ButlerSubset is a container for ButlerDataRefs.  It represents a
     collection of data ids that can be used to obtain datasets of the type
@@ -130,7 +127,7 @@ def __iter__(self):
         return ButlerSubsetIterator(self)
 
 
-class ButlerSubsetIterator(object):
+class ButlerSubsetIterator:
     """
     An iterator over the ButlerDataRefs in a ButlerSubset.
     """
@@ -146,7 +143,7 @@ def __next__(self):
         return ButlerDataRef(self.butlerSubset, next(self.iter))
 
 
-class ButlerDataRef(object):
+class ButlerDataRef:
     """
     A ButlerDataRef is a reference to a potential dataset or group of datasets
     that is portable between compatible dataset types.  As such, it can be

python/lsst/daf/persistence/dataId.py

@@ -21,15 +21,7 @@
 # the GNU General Public License along with this program.  If not,
 # see <http://www.lsstcorp.org/LegalNotices/>.
 #
-from past.builtins import basestring
-
-# On Python 3 collections.UserDict is iterable but on Python 2
-# we have to use UserDict.IterableUserDict. Since collections.UserDict
-# exists on Python 2 we try the Python 2 variant first.
-try:
-    from UserDict import IterableUserDict as UserDict
-except ImportError:
-    from collections import UserDict
+from collections import UserDict
 
 import copy
 
@@ -59,7 +51,7 @@ def __init__(self, initialdata=None, tag=None, **kwargs):
             self.tag = set()
 
         if tag is not None:
-            if isinstance(tag, basestring):
+            if isinstance(tag, str):
                 self.tag.update([tag])
             else:
                 try:

python/lsst/daf/persistence/fsScanner.py

@@ -22,17 +22,14 @@
 
 
 """This module provides the FsScanner class."""
-from __future__ import print_function
-from builtins import range
-from builtins import object
 
 import glob
 import os
 import re
 import sys
 
 
-class FsScanner(object):
+class FsScanner:
     """Class to scan a filesystem location for paths matching a template.
 
     Decomposes the resulting paths into fields and passes them to a callback

python/lsst/daf/persistence/mapper.py

@@ -21,15 +21,12 @@
 # the GNU General Public License along with this program.  If not,
 # see <http://www.lsstcorp.org/LegalNotices/>.
 #
-from builtins import object, super
-
-
 from . import Policy
 
 """This module defines the Mapper base class."""
 
 
-class Mapper(object):
+class Mapper:
     """Mapper is a base class for all mappers.
 
     Subclasses may define the following methods:

python/lsst/daf/persistence/policy.py

@@ -21,15 +21,10 @@
 # the GNU General Public License along with this program.  If not,
 # see <http://www.lsstcorp.org/LegalNotices/>.
 #
-from builtins import str
-from past.builtins import basestring
-from future.utils import with_metaclass
-
 import collections
 import collections.abc
 import copy
 import os
-import sys
 import warnings
 import yaml
 
@@ -39,20 +34,16 @@
 from yaml.representer import Representer
 yaml.add_representer(collections.defaultdict, Representer.represent_dict)
 
+
 # UserDict and yaml have defined metaclasses and Python 3 does not allow multiple
 # inheritance of classes with distinct metaclasses. We therefore have to
-# create a new baseclass that Policy can inherit from. This is because the metaclass
-# syntax differs between versions
+# create a new baseclass that Policy can inherit from.
+class _PolicyMeta(type(collections.UserDict), type(yaml.YAMLObject)):
+    pass
 
-if sys.version_info[0] >= 3:
-    class _PolicyMeta(type(collections.UserDict), type(yaml.YAMLObject)):
-        pass
 
-    class _PolicyBase(with_metaclass(_PolicyMeta, collections.UserDict, yaml.YAMLObject)):
-        pass
-else:
-    class _PolicyBase(collections.UserDict, yaml.YAMLObject):
-        pass
+class _PolicyBase(collections.UserDict, yaml.YAMLObject, metaclass=_PolicyMeta):
+    pass
 
 
 class Policy(_PolicyBase):
@@ -84,7 +75,7 @@ def __init__(self, other=None):
             self.update(other)
         elif isinstance(other, Policy):
             self.data = copy.deepcopy(other.data)
-        elif isinstance(other, basestring):
+        elif isinstance(other, str):
             # if other is a string, assume it is a file path.
             self.__initFromFile(other)
         elif isinstance(other, pexPolicy.Policy):
@@ -293,7 +284,7 @@ def asArray(self, name):
         :return:
         """
         val = self.get(name)
-        if isinstance(val, basestring):
+        if isinstance(val, str):
             val = [val]
         elif not isinstance(val, collections.abc.Container):
             val = [val]
@@ -373,7 +364,7 @@ def getStringArray(self, key):
         """
         warnings.warn("Deprecated. Use asArray()", DeprecationWarning)
         val = self.get(key)
-        if isinstance(val, basestring):
+        if isinstance(val, str):
             val = [val]
         elif not isinstance(val, collections.abc.Container):
             val = [val]

python/lsst/daf/persistence/posixStorage.py

@@ -21,7 +21,6 @@
 # the GNU General Public License along with this program.  If not,
 # see <http://www.lsstcorp.org/LegalNotices/>.
 #
-from past.builtins import basestring
 import sys
 import pickle
 import importlib
@@ -528,7 +527,7 @@ def readConfigStorage(butlerLocation):
             raise RuntimeError("No such config file: " + logLoc.locString())
         pythonType = butlerLocation.getPythonType()
         if pythonType is not None:
-            if isinstance(pythonType, basestring):
+            if isinstance(pythonType, str):
                 pythonType = doImport(pythonType)
         finalItem = pythonType()
         finalItem.load(logLoc.locString())
@@ -573,7 +572,7 @@ def readFitsStorage(butlerLocation):
     """
     pythonType = butlerLocation.getPythonType()
     if pythonType is not None:
-        if isinstance(pythonType, basestring):
+        if isinstance(pythonType, str):
             pythonType = doImport(pythonType)
     supportsOptions = hasattr(pythonType, "readFitsWithOptions")
     if not supportsOptions:
@@ -664,7 +663,7 @@ def readParquetStorage(butlerLocation):
 
         pythonType = butlerLocation.getPythonType()
         if pythonType is not None:
-            if isinstance(pythonType, basestring):
+            if isinstance(pythonType, str):
                 pythonType = doImport(pythonType)
 
         filename = logLoc.locString()
@@ -779,7 +778,7 @@ def readFitsCatalogStorage(butlerLocation):
     """
     pythonType = butlerLocation.getPythonType()
     if pythonType is not None:
-        if isinstance(pythonType, basestring):
+        if isinstance(pythonType, str):
             pythonType = doImport(pythonType)
     results = []
     additionalData = butlerLocation.getAdditionalData()

python/lsst/daf/persistence/readProxy.py

@@ -26,8 +26,6 @@
 
 """This module defines the ReadProxy class."""
 
-from __future__ import absolute_import
-
 from .persistence import ReadProxyBase