Drop PyPI mock package dep. on Python 3.3+

Use unittest.mock from the standard library where available.

Author: musicinmybrain

tests/ext/aiohttp/test_middleware.py

@@ -5,7 +5,10 @@
 """
 import asyncio
 from aws_xray_sdk import global_sdk_config
-from unittest.mock import patch
+try:
+    from unittest.mock import patch
+except ImportError:
+    from mock import patch  # Python 2
 
 from aiohttp import web
 from aiohttp.web_exceptions import HTTPUnauthorized

tests/ext/django/test_settings.py

@@ -1,4 +1,7 @@
-from unittest import mock
+try:
+    from unittest import mock
+except ImportError:
+    import mock  # Python 2
 
 import django
 from aws_xray_sdk import global_sdk_config
@@ -13,4 +16,4 @@
 class XRayConfigurationTestCase(TestCase):
     def test_sampler_can_be_configured(self):
         assert isinstance(settings.XRAY_RECORDER['SAMPLER'], LocalSampler)
-        assert isinstance(xray_recorder.sampler, LocalSampler)
+        assert isinstance(xray_recorder.sampler, LocalSampler)

tests/test_plugins.py

@@ -1,5 +1,8 @@
 from aws_xray_sdk.core.plugins.utils import get_plugin_modules
-from mock import patch
+try:
+    from unittest.mock import patch
+except ImportError:
+    from mock import patch  # Python 2
 
 supported_plugins = (
     'ec2_plugin',

tox.ini

@@ -36,7 +36,7 @@ deps =
     testing.postgresql
     testing.mysqld
     webtest
-    mock
+    mock ; python_version < '3.3'
 
     # Python2 only deps
     py{27}: enum34