diff --git a/git/cmd.py b/git/cmd.py
index 4dc76556e..5f96e33c9 100644
--- a/git/cmd.py
+++ b/git/cmd.py
@@ -528,13 +528,13 @@ def _terminate(self) -> None:
             try:
                 if proc.poll() is not None:
                     self.status = self._status_code_if_terminate or proc.poll()
-                    return None
+                    return
             except OSError as ex:
                 log.info("Ignored error after process had died: %r", ex)
 
             # It can be that nothing really exists anymore...
             if os is None or getattr(os, "kill", None) is None:
-                return None
+                return
 
             # Try to kill it.
             try:
diff --git a/git/config.py b/git/config.py
index 983d71e86..5708a7385 100644
--- a/git/config.py
+++ b/git/config.py
@@ -203,7 +203,8 @@ def __setitem__(self, key: str, value: _T) -> None:
     def add(self, key: str, value: Any) -> None:
         if key not in self:
             super().__setitem__(key, [value])
-            return None
+            return
+
         super().__getitem__(key).append(value)
 
     def setall(self, key: str, values: List[_T]) -> None:
@@ -579,7 +580,7 @@ def read(self) -> None:  # type: ignore[override]
         :raise IOError: If a file cannot be handled
         """
         if self._is_initialized:
-            return None
+            return
         self._is_initialized = True
 
         files_to_read: List[Union[PathLike, IO]] = [""]
@@ -697,7 +698,7 @@ def write(self) -> None:
             a file lock"""
         self._assure_writable("write")
         if not self._dirty:
-            return None
+            return
 
         if isinstance(self._file_or_files, (list, tuple)):
             raise AssertionError(
@@ -711,7 +712,7 @@ def write(self) -> None:
                 "Skipping write-back of configuration file as include files were merged in."
                 + "Set merge_includes=False to prevent this."
             )
-            return None
+            return
         # END stop if we have include files
 
         fp = self._file_or_files
diff --git a/git/index/base.py b/git/index/base.py
index 6c6462039..112ad3feb 100644
--- a/git/index/base.py
+++ b/git/index/base.py
@@ -166,7 +166,7 @@ def _set_cache_(self, attr: str) -> None:
             except OSError:
                 # In new repositories, there may be no index, which means we are empty.
                 self.entries: Dict[Tuple[PathLike, StageType], IndexEntry] = {}
-                return None
+                return
             # END exception handling
 
             try:
@@ -1210,9 +1210,9 @@ def checkout(
         def handle_stderr(proc: "Popen[bytes]", iter_checked_out_files: Iterable[PathLike]) -> None:
             stderr_IO = proc.stderr
             if not stderr_IO:
-                return None  # Return early if stderr empty.
-            else:
-                stderr_bytes = stderr_IO.read()
+                return  # Return early if stderr empty.
+
+            stderr_bytes = stderr_IO.read()
             # line contents:
             stderr = stderr_bytes.decode(defenc)
             # git-checkout-index: this already exists
diff --git a/git/index/fun.py b/git/index/fun.py
index eaf5f51ff..97f2c88e6 100644
--- a/git/index/fun.py
+++ b/git/index/fun.py
@@ -83,7 +83,7 @@ def run_commit_hook(name: str, index: "IndexFile", *args: str) -> None:
     """
     hp = hook_path(name, index.repo.git_dir)
     if not os.access(hp, os.X_OK):
-        return None
+        return
 
     env = os.environ.copy()
     env["GIT_INDEX_FILE"] = safe_decode(str(index.path))
diff --git a/git/objects/tree.py b/git/objects/tree.py
index 4d94a5d24..a08adf48b 100644
--- a/git/objects/tree.py
+++ b/git/objects/tree.py
@@ -68,7 +68,7 @@ def git_cmp(t1: TreeCacheTup, t2: TreeCacheTup) -> int:
 
 def merge_sort(a: List[TreeCacheTup], cmp: Callable[[TreeCacheTup, TreeCacheTup], int]) -> None:
     if len(a) < 2:
-        return None
+        return
 
     mid = len(a) // 2
     lefthalf = a[:mid]
diff --git a/git/objects/util.py b/git/objects/util.py
index 3021fec39..3e8f8dcc9 100644
--- a/git/objects/util.py
+++ b/git/objects/util.py
@@ -500,8 +500,8 @@ def addToStack(
             depth: int,
         ) -> None:
             lst = self._get_intermediate_items(item)
-            if not lst:  # empty list
-                return None
+            if not lst:  # Empty list
+                return
             if branch_first:
                 stack.extendleft(TraverseNT(depth, i, src_item) for i in lst)
             else:
diff --git a/git/util.py b/git/util.py
index 01cdcf773..aaf662060 100644
--- a/git/util.py
+++ b/git/util.py
@@ -644,7 +644,7 @@ def _parse_progress_line(self, line: AnyStr) -> None:
             self.line_dropped(line_str)
             # Note: Don't add this line to the other lines, as we have to silently
             # drop it.
-            return None
+            return
         # END handle op code
 
         # Figure out stage.