diff --git a/tests/helpers/stubs.py b/tests/helpers/stubs.py
index cb3c85896..d2c0fd746 100644
--- a/tests/helpers/stubs.py
+++ b/tests/helpers/stubs.py
@@ -131,7 +131,7 @@ class FakeUrl:
 
     """QUrl stub which provides .path(), isValid() and host()."""
 
-    def __init__(self, path=None, valid=True, host=None, url=None, scheme = None):
+    def __init__(self, path=None, valid=True, host=None, url=None, scheme=None):
         self.path = mock.Mock(return_value=path)
         self.isValid = mock.Mock(returl_value=valid)
         self.host = mock.Mock(returl_value=host)