diff --git a/stdlib/2.7/subprocess.pyi b/stdlib/2.7/subprocess.pyi
index f3b1eb4d5..8286e83d0 100644
--- a/stdlib/2.7/subprocess.pyi
+++ b/stdlib/2.7/subprocess.pyi
@@ -87,8 +87,7 @@ class Popen:
 
     def poll(self) -> int: ...
     def wait(self) -> int: ...
-    # Return str/bytes
-    def communicate(self, input: Union[str, unicode] = ...) -> Tuple[str, str]: ...
+    def communicate(self, input: Union[bytes, unicode] = ...) -> Tuple[Optional[bytes], Optional[bytes]]: ...
     def send_signal(self, signal: int) -> None: ...
     def terminate(self) -> None: ...
     def kill(self) -> None: ...