fix typing

Author: blink1073

pymongo/asynchronous/pool.py

@@ -1028,6 +1028,7 @@ def _handle_connection_error(self, error: BaseException) -> None:
         # Look for errors of type AutoReconnect and add error labels if appropriate.
         if self.is_sdam or type(error) not in (AutoReconnect, NetworkTimeout):
             return
+        assert isinstance(error, AutoReconnect)  # Appease type checker.
         error._add_error_label("SystemOverloadedError")
         error._add_error_label("RetryableError")
 

pymongo/synchronous/pool.py

@@ -1024,6 +1024,7 @@ def _handle_connection_error(self, error: BaseException) -> None:
         # Look for errors of type AutoReconnect and add error labels if appropriate.
         if self.is_sdam or type(error) not in (AutoReconnect, NetworkTimeout):
             return
+        assert isinstance(error, AutoReconnect)  # Appease type checker.
         error._add_error_label("SystemOverloadedError")
         error._add_error_label("RetryableError")