diff --git a/zulip/integrations/rss/rss-bot b/zulip/integrations/rss/rss-bot
index 93c740e..69f38c6 100755
--- a/zulip/integrations/rss/rss-bot
+++ b/zulip/integrations/rss/rss-bot
@@ -14,7 +14,7 @@ import os
 import re
 import sys
 import time
-import urllib
+import urllib.parse
 from typing import Dict, List, Tuple, Any
 
 import feedparser
diff --git a/zulip/tests/test_default_arguments.py b/zulip/tests/test_default_arguments.py
index 0b95db2..6263d3a 100755
--- a/zulip/tests/test_default_arguments.py
+++ b/zulip/tests/test_default_arguments.py
@@ -2,16 +2,13 @@
 
 import argparse
 import os
-import six
+import io
 import unittest
 import zulip
 
 from unittest import TestCase
 from zulip import ZulipError
-if six.PY2:
-    from mock import patch
-else:
-    from unittest.mock import patch
+from unittest.mock import patch
 
 class TestDefaultArguments(TestCase):
 
@@ -19,7 +16,7 @@ class TestDefaultArguments(TestCase):
         # type: () -> None
         parser = zulip.add_default_arguments(argparse.ArgumentParser(usage="lorem ipsum"))
         with self.assertRaises(SystemExit) as cm:  # type: ignore # error: "assertRaises" doesn't match argument types
-            with patch('sys.stderr', new=six.StringIO()) as mock_stderr:
+            with patch('sys.stderr', new=io.StringIO()) as mock_stderr:
                 parser.parse_args(['invalid argument'])
         self.assertEqual(cm.exception.code, 2)
         # Assert that invalid arguments exit with printing the full usage (non-standard behavior)
diff --git a/zulip/zulip/__init__.py b/zulip/zulip/__init__.py
index 7bdd4b6..e2efe4d 100644
--- a/zulip/zulip/__init__.py
+++ b/zulip/zulip/__init__.py
@@ -15,10 +15,9 @@ import types
 from distutils.version import LooseVersion
 
 import distro
-from six.moves.configparser import SafeConfigParser
-from six.moves import urllib
+from configparser import SafeConfigParser
+import urllib.parse
 import logging
-import six
 from typing import Any, Callable, Dict, Iterable, IO, List, Mapping, Optional, Text, Tuple, Union
 
 __version__ = "0.6.4"
@@ -473,7 +472,7 @@ class Client(object):
         request = {}
         req_files = []
 
-        for (key, val) in six.iteritems(orig_request):
+        for (key, val) in orig_request.items():
             if isinstance(val, str) or isinstance(val, Text):
                 request[key] = val
             else: