diff --git a/aioresponses/core.py b/aioresponses/core.py
index 09ff03b..9096ced 100644
--- a/aioresponses/core.py
+++ b/aioresponses/core.py
@@ -1,21 +1,16 @@
 # -*- coding: utf-8 -*-
 
 import asyncio
-import collections
 import json
-
-from functools import wraps
-from multidict import CIMultiDict
-
-try:
-    from typing import Dict, Tuple
-except ImportError:
-    Dict = dict
-    Tuple = tuple
+from typing import Dict, Tuple
 from unittest.mock import patch
 from urllib.parse import urlparse, parse_qsl, urlencode
 
+import collections
 from aiohttp import hdrs, ClientResponse, ClientConnectionError, client
+from functools import wraps
+from multidict import CIMultiDict
+
 from .compat import URL
 
 
@@ -133,8 +128,8 @@ def add(self, url: str, method: str = hdrs.METH_GET, status: int = 200,
             body: str = '',
             exception: 'Exception' = None,
             content_type: str = 'application/json',
-            payload: Dict=None,
-            headers: Dict=None) -> None:
+            payload: Dict = None,
+            headers: Dict = None) -> None:
         self._responses.append(UrlResponse(
             url,
             method=method,
@@ -166,9 +161,10 @@ def _request_mock(self, orig_self: client.ClientSession,
                       **kwargs: Dict) -> 'ClientResponse':
         """Return mocked response object or raise connection error."""
         for prefix in self._passthrough:
-            if url.startswith(prefix):
-                return self.patcher.temp_original(
-                    orig_self, method, url, *args, **kwargs)
+            if str(url).startswith(prefix):
+                return (yield from self.patcher.temp_original(
+                    orig_self, method, url, *args, **kwargs
+                ))
 
         response = self.match(method, url)
         if response is None:
diff --git a/requirements-dev.txt b/requirements-dev.txt
index 3457f06..291ce54 100644
--- a/requirements-dev.txt
+++ b/requirements-dev.txt
@@ -1,11 +1,11 @@
 pip
-bumpversion
 wheel
-watchdog
-flake8
-tox
-coverage
-Sphinx
-nose2
-cov-core
-ddt
+watchdog==0.8.3
+flake8==3.3.0
+tox==2.7.0
+coverage==4.4.1
+Sphinx==1.5.6
+nose2==0.6.5
+cov-core==1.15.0
+ddt==1.1.1
+typing
\ No newline at end of file
diff --git a/setup.cfg b/setup.cfg
index f8aeb0e..fa25d8d 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -25,19 +25,6 @@ all_files = 1
 build-dir = docs/build
 source-dir = docs/source
 
-[bumpversion]
-current_version = 0.1.0
-commit = True
-tag = True
-
-[bumpversion:file:setup.py]
-search = version='{current_version}'
-replace = version='{new_version}'
-
-[bumpversion:file:aioresponses/__init__.py]
-search = __version__ = '{current_version}'
-replace = __version__ = '{new_version}'
-
 [bdist_wheel]
 universal = 1
 
diff --git a/tests/test_aioresponses.py b/tests/test_aioresponses.py
index c0a4351..9a65ff8 100644
--- a/tests/test_aioresponses.py
+++ b/tests/test_aioresponses.py
@@ -1,12 +1,14 @@
 # -*- coding: utf-8 -*-
 import asyncio
 from unittest.case import TestCase
-from unittest.mock import patch, Mock
+from unittest.mock import patch
 
 from aiohttp import hdrs
 from aiohttp.client import ClientSession
 from aiohttp.client_reqrep import ClientResponse
 
+from aioresponses.compat import URL
+
 try:
     from aiohttp.errors import ClientConnectionError, HttpProcessingError
 except ImportError:
@@ -136,13 +138,23 @@ def test_multiple_requests(self):
             self.assertIn(key, m.requests)
             self.assertEqual(len(m.requests[key]), 3)
             self.assertEqual(m.requests[key][0].args, tuple())
-            self.assertEqual(m.requests[key][0].kwargs, {'allow_redirects': True})
+            self.assertEqual(m.requests[key][0].kwargs,
+                             {'allow_redirects': True})
 
-    def test_passthrough(self):
-        self.session._request = mocked = Mock()
-        mocked.side_effect = asyncio.coroutine(
-            lambda method, url, *args, **kwargs: None)
-        with aioresponses(passthrough=['http://example.com']) as m:
-            resp = self.loop.run_until_complete(self.session.get(self.url))
-            mocked.assert_called_once_with(
-                'GET', 'http://example.com/api', allow_redirects=True)
+    def test_address_as_instance_of_url_combined_with_pass_through(self):
+        external_api = 'http://google.com'
+
+        @asyncio.coroutine
+        def doit():
+            api_resp = yield from self.session.get(self.url)
+            # we have to hit actual url,
+            # otherwise we do not test pass through option properly
+            ext_rep = yield from self.session.get(URL(external_api))
+            return api_resp, ext_rep
+
+        with aioresponses(passthrough=[external_api]) as m:
+            m.get(self.url, status=200)
+            api, ext = self.loop.run_until_complete(doit())
+
+            self.assertEqual(api.status, 200)
+            self.assertEqual(ext.status, 200)
diff --git a/tox.ini b/tox.ini
index ce11420..283480c 100644
--- a/tox.ini
+++ b/tox.ini
@@ -2,7 +2,7 @@
 envlist =
     flake8,
     coverage,
-    {py34,py35}-aiohttp{10,11,12,master}
+    {py34,py35}-aiohttp{10,11,12,13,20,master}
 skipsdist=True
 
 [testenv:flake8]