diff --git a/cloudbaseinit/plugins/windows/userdata.py b/cloudbaseinit/plugins/windows/userdata.py
index dda80958..a2bc5386 100644
--- a/cloudbaseinit/plugins/windows/userdata.py
+++ b/cloudbaseinit/plugins/windows/userdata.py
@@ -28,7 +28,7 @@ LOG = logging.getLogger(__name__)
 
 
 class UserDataPlugin(base.BasePlugin):
-    _part_handler_content_type = "text/part-handler"
+    _PART_HANDLER_CONTENT_TYPE = "text/part-handler"
     _GZIP_MAGIC_NUMBER = '\x1f\x8b'
 
     def execute(self, service, shared_data):
@@ -99,7 +99,7 @@ class UserDataPlugin(base.BasePlugin):
                     LOG.debug("Executing userdata plugin: %s" %
                               user_data_plugin.__class__.__name__)
 
-                    if content_type == self._part_handler_content_type:
+                    if content_type == self._PART_HANDLER_CONTENT_TYPE:
                         new_user_handlers = user_data_plugin.process(part)
                         self._add_part_handlers(user_data_plugins,
                                                 user_handlers,
diff --git a/cloudbaseinit/tests/plugins/windows/test_userdata.py b/cloudbaseinit/tests/plugins/windows/test_userdata.py
index 787fb9ba..892dfacc 100644
--- a/cloudbaseinit/tests/plugins/windows/test_userdata.py
+++ b/cloudbaseinit/tests/plugins/windows/test_userdata.py
@@ -135,7 +135,7 @@ class UserDataPluginTest(unittest.TestCase):
         mock_user_handlers.get.side_effect = [handler_func]
         mock_user_data_plugins.get.side_effect = [user_data_plugin]
         if content_type:
-            _content_type = self._userdata._part_handler_content_type
+            _content_type = self._userdata._PART_HANDLER_CONTENT_TYPE
             mock_part.get_content_type.return_value = _content_type
         else:
             _content_type = 'other content type'