diff --git a/IPython/core/tests/test_events.py b/IPython/core/tests/test_events.py
index 3053a70..7143c82 100644
--- a/IPython/core/tests/test_events.py
+++ b/IPython/core/tests/test_events.py
@@ -1,8 +1,5 @@
 import unittest
-try:  # Python 3.3 +
-    from unittest.mock import Mock
-except ImportError:
-    from mock import Mock
+from unittest.mock import Mock
 
 from IPython.core import events
 import IPython.testing.tools as tt
diff --git a/IPython/core/tests/test_interactiveshell.py b/IPython/core/tests/test_interactiveshell.py
index 9236b7a..a491afe 100644
--- a/IPython/core/tests/test_interactiveshell.py
+++ b/IPython/core/tests/test_interactiveshell.py
@@ -16,10 +16,8 @@ import shutil
 import sys
 import tempfile
 import unittest
-try:
-    from unittest import mock
-except ImportError:
-    import mock
+from unittest import mock
+
 from os.path import join
 
 import nose.tools as nt
diff --git a/IPython/core/tests/test_paths.py b/IPython/core/tests/test_paths.py
index 20257ba..8f09001 100644
--- a/IPython/core/tests/test_paths.py
+++ b/IPython/core/tests/test_paths.py
@@ -4,11 +4,7 @@ import shutil
 import sys
 import tempfile
 import warnings
-
-try:                    # Python 3
-    from unittest.mock import patch
-except ImportError:     # Python 2
-    from mock import patch
+from unittest.mock import patch
 
 import nose.tools as nt
 from testpath import modified_env, assert_isdir, assert_isfile
diff --git a/IPython/core/tests/test_run.py b/IPython/core/tests/test_run.py
index d684990..c654ff8 100644
--- a/IPython/core/tests/test_run.py
+++ b/IPython/core/tests/test_run.py
@@ -20,11 +20,7 @@ import random
 import sys
 import textwrap
 import unittest
-
-try:
-    from unittest.mock import patch
-except ImportError:
-    from mock import patch
+from unittest.mock import patch
 
 import nose.tools as nt
 from nose import SkipTest
diff --git a/IPython/core/tests/test_ultratb.py b/IPython/core/tests/test_ultratb.py
index c9c86c0..f89ebb2 100644
--- a/IPython/core/tests/test_ultratb.py
+++ b/IPython/core/tests/test_ultratb.py
@@ -7,11 +7,7 @@ import os.path
 from textwrap import dedent
 import traceback
 import unittest
-
-try:
-    from unittest import mock
-except ImportError:
-    import mock    # Python 2
+from unittest import mock
 
 from ..ultratb import ColorTB, VerboseTB, find_recursion
 
diff --git a/IPython/lib/latextools.py b/IPython/lib/latextools.py
index c3230dd..2b1b2c7 100644
--- a/IPython/lib/latextools.py
+++ b/IPython/lib/latextools.py
@@ -9,6 +9,7 @@ import os
 import tempfile
 import shutil
 import subprocess
+from base64 import encodebytes
 
 from IPython.utils.process import find_cmd, FindCmdError
 from traitlets.config import get_config
@@ -16,11 +17,6 @@ from traitlets.config.configurable import SingletonConfigurable
 from traitlets import List, Bool, Unicode
 from IPython.utils.py3compat import cast_unicode, cast_unicode_py2 as u, PY3
 
-try: # Py3
-    from base64 import encodebytes
-except ImportError: # Py2
-    from base64 import encodestring as encodebytes
-
 
 class LaTeXTool(SingletonConfigurable):
     """An object to store configuration of the LaTeX tool."""
diff --git a/IPython/lib/tests/test_latextools.py b/IPython/lib/tests/test_latextools.py
index 6d0d1a1..2772784 100644
--- a/IPython/lib/tests/test_latextools.py
+++ b/IPython/lib/tests/test_latextools.py
@@ -3,12 +3,7 @@
 
 # Copyright (c) IPython Development Team.
 # Distributed under the terms of the Modified BSD License.
-
-try:
-    from unittest.mock import patch
-except ImportError:
-    from mock import patch
-
+from unittest.mock import patch
 import nose.tools as nt
 
 from IPython.lib import latextools
diff --git a/IPython/utils/tests/test_path.py b/IPython/utils/tests/test_path.py
index cc48fe8..67018d4 100644
--- a/IPython/utils/tests/test_path.py
+++ b/IPython/utils/tests/test_path.py
@@ -11,19 +11,12 @@ import sys
 import tempfile
 import warnings
 from contextlib import contextmanager
-
-try:  # Python 3.3+
-    from unittest.mock import patch
-except ImportError:
-    from mock import patch
-
+from unittest.mock import patch
 from os.path import join, abspath, split
 
-from nose import SkipTest
+from nose import SkipTest, with_setup
 import nose.tools as nt
 
-from nose import with_setup
-
 import IPython
 from IPython import paths
 from IPython.testing import decorators as dec