diff --git a/Lib/numbers.py b/Lib/numbers.py
index d7c8931..201dc3c 100644
--- a/Lib/numbers.py
+++ b/Lib/numbers.py
@@ -189,7 +189,7 @@
         raise NotImplementedError
 
     @abstractmethod
-    def __round__(self, ndigits:"Integral"=None):
+    def __round__(self, ndigits=None):
         """Rounds self to ndigits decimal places, defaulting to 0.
 
         If ndigits is omitted or None, returns an Integral, otherwise