--- rsa/_version133.py
+++ rsa/_version133.py
@@ -18,7 +18,12 @@ __version__ = '1.3.3'
 # NOTE: Python's modulo can return negative numbers. We compensate for
 # this behaviour using the abs() function
 
-from cPickle import dumps, loads
+try:
+    import cPickle as pickle
+except:
+    import pickle
+from pickle import dumps, loads
+
 import base64
 import math
 import os
--- tests/constants.py
+++ tests/constants.py
@@ -3,7 +3,7 @@
 from rsa._compat import have_python3
 
 if have_python3:
-    from py3kconstants import *
+    from tests.py3kconstants import *
 else:
     from py2kconstants import *
 
--- tests/test_strings.py
+++ tests/test_strings.py
@@ -6,7 +6,7 @@ import unittest2
 
 import rsa
 
-from constants import unicode_string
+from tests.constants import unicode_string
 
 class StringTest(unittest2.TestCase):