diff --git a/utils/checkstyle.py b/utils/checkstyle.py
index 0e9659e98518..fb9366f8095d 100755
--- a/utils/checkstyle.py
+++ b/utils/checkstyle.py
@@ -203,23 +203,23 @@ class CommitFile:
 class Commit:
     def __init__(self, commit):
         self.commit = commit
-        self.__parse()
+        self._parse()
 
-    def __parse(self):
+    def _parse(self):
         # Get the commit title and list of files.
         ret = subprocess.run(['git', 'show', '--pretty=oneline', '--name-status',
                               self.commit],
                              stdout=subprocess.PIPE).stdout.decode('utf-8')
         files = ret.splitlines()
-        self.__files = [CommitFile(f) for f in files[1:]]
-        self.__title = files[0]
+        self._files = [CommitFile(f) for f in files[1:]]
+        self._title = files[0]
 
     def files(self, filter='AM'):
-        return [f.filename for f in self.__files if f.status in filter]
+        return [f.filename for f in self._files if f.status in filter]
 
     @property
     def title(self):
-        return self.__title
+        return self._title
 
     def get_diff(self, top_level, filename):
         diff = subprocess.run(['git', 'diff', '%s~..%s' % (self.commit, self.commit),
@@ -236,11 +236,11 @@ class StagedChanges(Commit):
     def __init__(self):
         Commit.__init__(self, '')
 
-    def __parse(self):
+    def _parse(self):
         ret = subprocess.run(['git', 'diff', '--staged', '--name-status'],
                              stdout=subprocess.PIPE).stdout.decode('utf-8')
-        self.__title = "Staged changes"
-        self.__files = [CommitFile(f) for f in ret.splitlines()]
+        self._title = "Staged changes"
+        self._files = [CommitFile(f) for f in ret.splitlines()]
 
     def get_diff(self, top_level, filename):
         diff = subprocess.run(['git', 'diff', '--staged', '--',
@@ -253,15 +253,15 @@ class Amendment(StagedChanges):
     def __init__(self):
         StagedChanges.__init__(self)
 
-    def __parse(self):
+    def _parse(self):
         # Create a title using HEAD commit
         ret = subprocess.run(['git', 'show', '--pretty=oneline', '--no-patch'],
                              stdout=subprocess.PIPE).stdout.decode('utf-8')
-        self.__title = 'Amendment of ' + ret.strip()
+        self._title = 'Amendment of ' + ret.strip()
         # Extract the list of modified files
         ret = subprocess.run(['git', 'diff', '--staged', '--name-status', 'HEAD~'],
                              stdout=subprocess.PIPE).stdout.decode('utf-8')
-        self.__files = [CommitFile(f) for f in ret.splitlines()]
+        self._files = [CommitFile(f) for f in ret.splitlines()]
 
     def get_diff(self, top_level, filename):
         diff = subprocess.run(['git', 'diff', '--staged', 'HEAD~', '--',