diff --git a/.deepsource.toml b/.deepsource.toml
new file mode 100644
index 000000000..1dbc38786
--- /dev/null
+++ b/.deepsource.toml
@@ -0,0 +1,15 @@
+version = 1
+
+test_patterns = [
+  'git/test/**/test_*.py'
+]
+
+exclude_patterns = [
+  'doc/**',
+  'etc/sublime-text'
+]
+
+[[analyzers]]
+name = 'python'
+enabled = true
+runtime_version = '2.x.x'
diff --git a/git/objects/submodule/base.py b/git/objects/submodule/base.py
index a75826eb3..384f7c5fc 100644
--- a/git/objects/submodule/base.py
+++ b/git/objects/submodule/base.py
@@ -864,9 +864,8 @@ def remove(self, module=True, force=False, configuration=True, dry_run=False):
                         rmtree(wtd)
                     except Exception as ex:
                         if HIDE_WINDOWS_KNOWN_ERRORS:
-                            raise SkipTest("FIXME: fails with: PermissionError\n  %s", ex)
-                        else:
-                            raise
+                            raise SkipTest("FIXME: fails with: PermissionError\n  {}".format(ex))
+                        raise
                 # END delete tree if possible
             # END handle force
 
diff --git a/git/test/test_config.py b/git/test/test_config.py
index 93f94748a..83e510be4 100644
--- a/git/test/test_config.py
+++ b/git/test/test_config.py
@@ -38,7 +38,7 @@ def setUp(self):
     def tearDown(self):
         for lfp in glob.glob(_tc_lock_fpaths):
             if osp.isfile(lfp):
-                raise AssertionError('Previous TC left hanging git-lock file: %s', lfp)
+                raise AssertionError('Previous TC left hanging git-lock file: {}'.format(lfp))
 
     def _to_memcache(self, file_path):
         with open(file_path, "rb") as fp:
diff --git a/git/test/test_git.py b/git/test/test_git.py
index 4a189267e..357d9edb3 100644
--- a/git/test/test_git.py
+++ b/git/test/test_git.py
@@ -134,15 +134,18 @@ def test_it_accepts_environment_variables(self):
 
     def test_persistent_cat_file_command(self):
         # read header only
-        import subprocess as sp
         hexsha = "b2339455342180c7cc1e9bba3e9f181f7baa5167"
-        g = self.git.cat_file(batch_check=True, istream=sp.PIPE, as_process=True)
+        g = self.git.cat_file(
+            batch_check=True, istream=subprocess.PIPE, as_process=True
+        )
         g.stdin.write(b"b2339455342180c7cc1e9bba3e9f181f7baa5167\n")
         g.stdin.flush()
         obj_info = g.stdout.readline()
 
         # read header + data
-        g = self.git.cat_file(batch=True, istream=sp.PIPE, as_process=True)
+        g = self.git.cat_file(
+            batch=True, istream=subprocess.PIPE, as_process=True
+        )
         g.stdin.write(b"b2339455342180c7cc1e9bba3e9f181f7baa5167\n")
         g.stdin.flush()
         obj_info_two = g.stdout.readline()
@@ -160,7 +163,7 @@ def test_persistent_cat_file_command(self):
 
         # same can be achieved using the respective command functions
         hexsha, typename, size = self.git.get_object_header(hexsha)
-        hexsha, typename_two, size_two, data = self.git.get_object_data(hexsha)  # @UnusedVariable
+        hexsha, typename_two, size_two, _ = self.git.get_object_data(hexsha)
         self.assertEqual(typename, typename_two)
         self.assertEqual(size, size_two)
 
@@ -264,7 +267,7 @@ def test_environment(self, rw_dir):
                 remote.fetch()
             except GitCommandError as err:
                 if sys.version_info[0] < 3 and is_darwin:
-                    self.assertIn('ssh-orig, ' in str(err))
+                    self.assertIn('ssh-orig', str(err))
                     self.assertEqual(err.status, 128)
                 else:
                     self.assertIn('FOO', str(err))
diff --git a/git/test/test_repo.py b/git/test/test_repo.py
index c74d4ef41..94f9fdf80 100644
--- a/git/test/test_repo.py
+++ b/git/test/test_repo.py
@@ -90,7 +90,7 @@ def setUp(self):
     def tearDown(self):
         for lfp in glob.glob(_tc_lock_fpaths):
             if osp.isfile(lfp):
-                raise AssertionError('Previous TC left hanging git-lock file: %s', lfp)
+                raise AssertionError('Previous TC left hanging git-lock file: {}'.format(lfp))
         import gc
         gc.collect()
 
diff --git a/git/util.py b/git/util.py
index 7ca0564eb..b3963d3bf 100644
--- a/git/util.py
+++ b/git/util.py
@@ -98,9 +98,8 @@ def onerror(func, path, exc_info):
             func(path)  # Will scream if still not possible to delete.
         except Exception as ex:
             if HIDE_WINDOWS_KNOWN_ERRORS:
-                raise SkipTest("FIXME: fails with: PermissionError\n  %s", ex)
-            else:
-                raise
+                raise SkipTest("FIXME: fails with: PermissionError\n  {}".format(ex))
+            raise
 
     return shutil.rmtree(path, False, onerror)