diff --git a/pbr/tests/test_commands.py b/pbr/tests/test_commands.py
index 51e27116..7cf3fa91 100644
--- a/pbr/tests/test_commands.py
+++ b/pbr/tests/test_commands.py
@@ -78,7 +78,7 @@ class TestCommands(base.BaseTestCase):
         stdout, stderr, return_code = self.run_pbr('freeze')
         self.assertEqual(0, return_code)
         pkgs = []
-        for l in stdout.split('\n'):
-            pkgs.append(l.split('==')[0].lower())
+        for line in stdout.split('\n'):
+            pkgs.append(line.split('==')[0].lower())
         pkgs_sort = sorted(pkgs[:])
         self.assertEqual(pkgs_sort, pkgs)
diff --git a/pbr/tests/test_util.py b/pbr/tests/test_util.py
index 1cbb2d2a..a9fdf6e4 100644
--- a/pbr/tests/test_util.py
+++ b/pbr/tests/test_util.py
@@ -146,7 +146,7 @@ class TestKeywordsParsingScenarios(base.BaseTestCase):
                     three
                 """,  # noqa: E501
             'expected_keywords': ['one', 'two', 'three'],
-            },
+        },
         ),
         ('inline_keywords', {
             'config_text': """
diff --git a/pbr/util.py b/pbr/util.py
index 1e9fdc49..60b7cd7e 100644
--- a/pbr/util.py
+++ b/pbr/util.py
@@ -548,7 +548,7 @@ def get_extension_modules(config):
         else:
             # Backwards compatibility for old syntax; don't use this though
             labels = section.split('=', 1)
-        labels = [l.strip() for l in labels]
+        labels = [label.strip() for label in labels]
         if (len(labels) == 2) and (labels[0] == 'extension'):
             ext_args = {}
             for field in EXTENSION_FIELDS:
diff --git a/test-requirements.txt b/test-requirements.txt
index 0358a796..a3c5a110 100644
--- a/test-requirements.txt
+++ b/test-requirements.txt
@@ -4,7 +4,7 @@
 
 wheel>=0.32.0 # MIT
 fixtures>=3.0.0 # Apache-2.0/BSD
-hacking>=1.1.0,<1.2.0 # Apache-2.0
+hacking>=1.1.0,<4.0.0 # Apache-2.0
 mock>=2.0.0 # BSD
 six>=1.12.0 # MIT
 stestr>=2.1.0,<3.0;python_version=='2.7' # Apache-2.0