diff --git a/tests/test_interfaces.py b/tests/test_interfaces.py
index 302edb93e3bf..3e0933447fc4 100644
--- a/tests/test_interfaces.py
+++ b/tests/test_interfaces.py
@@ -58,7 +58,7 @@ def property(self):
     def test_signature_mismatch(self):
         class SimpleInterface(metaclass=abc.ABCMeta):
             @abc.abstractmethod
-            def method(self, other: object) -> int:
+            def method(self, other: object):
                 """Method with signature"""
 
         class ClassWithoutSignature:
@@ -66,7 +66,7 @@ def method(self, other):
                 """Method without signature"""
 
         class ClassWithSignature:
-            def method(self, other: object) -> int:
+            def method(self, other: object):
                 """Method with signature"""
 
         verify_interface(SimpleInterface, ClassWithoutSignature)