diff --git a/common/spinner.py b/common/spinner.py
index da8084037e..370d54c815 100644
--- a/common/spinner.py
+++ b/common/spinner.py
@@ -40,7 +40,7 @@ class Spinner():
     self.close()
 
 
-class FakeSpinner():
+class FakeSpinner(Spinner):
   def __init__(self):
     pass
 
diff --git a/common/text_window.py b/common/text_window.py
index 0d94bc7470..50fdcb6440 100755
--- a/common/text_window.py
+++ b/common/text_window.py
@@ -43,7 +43,7 @@ class TextWindow():
     self.close()
 
 
-class FakeTextWindow():
+class FakeTextWindow(TextWindow):
   def __init__(self, s):
     pass