diff --git a/reviewrot/__init__.py b/reviewrot/__init__.py
index af0eaaa..d15ed7a 100644
--- a/reviewrot/__init__.py
+++ b/reviewrot/__init__.py
@@ -400,7 +400,7 @@ def dict_constructor(loader, node):
     #  format the output to print a blank scalar rather than null
     def represent_none(self, _):
         """TODO: docstring goes here."""
-        return self.represent_scalar("tag:yaml.org,2002:null", u"")
+        return self.represent_scalar("tag:yaml.org,2002:null", "")
 
     yaml.add_representer(type(None), represent_none)
 
diff --git a/reviewrot/githubstack.py b/reviewrot/githubstack.py
index d97fb56..690d9a0 100644
--- a/reviewrot/githubstack.py
+++ b/reviewrot/githubstack.py
@@ -193,11 +193,19 @@ def get_last_comment(self, pr):
         last_issue_comment = None
         last_comment = None
 
-        if review_comments.totalCount > 0:
+        try:
+            # review_comments.totalCount may return a non-zero value when
+            # the list of comments is actually empty :(
             last_review_comment = review_comments.reversed[0]
+        except IndexError:
+            pass
 
-        if issue_comments.totalCount > 0:
+        try:
+            # issue_comments.totalCount may return a non-zero value when
+            # the list of comments is actually empty :(
             last_issue_comment = issue_comments.reversed[0]
+        except IndexError:
+            pass
 
         # check which is newer if pr has both types of comments
         if last_issue_comment and last_review_comment:
diff --git a/reviewrot/pagurestack.py b/reviewrot/pagurestack.py
index e322770..a125c9b 100644
--- a/reviewrot/pagurestack.py
+++ b/reviewrot/pagurestack.py
@@ -216,7 +216,7 @@ def _avatar(self, username, ssl_verify=True):
                 "Fallback to construct based on username"
             )
             query = urllib.parse.urlencode(avatar_query)
-            openid = u"http://%s.id.fedoraproject.org/" % username
+            openid = "http://%s.id.fedoraproject.org/" % username
             idx = hashlib.sha256(openid.encode("utf-8")).hexdigest()
             avatar_url = "https://seccdn.libravatar.org/avatar/%s?%s" % (idx, query)
 
diff --git a/test/github_tests/mock_github.py b/test/github_tests/mock_github.py
index 025fb25..21b058d 100644
--- a/test/github_tests/mock_github.py
+++ b/test/github_tests/mock_github.py
@@ -35,22 +35,24 @@ class MockValueOlder:
 class MockGithubComments:
     """Mocks Github Comments object."""
 
-    totalCount = int(1)
+    totalCount = int(1)  # noqa: N815
     reversed = [MockValue]
 
 
 class MockGithubCommentsOlder:
     """Mocks Github Comments object."""
 
-    totalCount = int(1)
+    totalCount = int(1)  # noqa: N815
     reversed = [MockValueOlder]
 
 
 class MockGithubCommentsEmpty:
     """Mocks Github Comment object with no comments."""
 
-    totalCount = 0
-    reversed = [MockValue]
+    # Simulate the bug from the PyGithub package, where
+    # totalCount is non-zero when there are no comments.
+    totalCount = int(2)  # noqa: N815
+    reversed = []
 
 
 class MockPull:
diff --git a/test/github_tests/test_github.py b/test/github_tests/test_github.py
index bb1ec05..d79e921 100644
--- a/test/github_tests/test_github.py
+++ b/test/github_tests/test_github.py
@@ -75,8 +75,7 @@ def test_get_last_comment_nothing(self, mock_lastcomment):
         # Call function
         response = GithubService().get_last_comment(mock_pr)
 
-        # Validate function calls and response
-        mock_lastcomment.assert_not_called()
+        # Validate function response
         self.assertIsNone(response)
 
     @patch(PATH + "GithubService.check_request_state")