diff --git a/stable_baselines3/common/monitor.py b/stable_baselines3/common/monitor.py
index 5253954..f421a4d 100644
--- a/stable_baselines3/common/monitor.py
+++ b/stable_baselines3/common/monitor.py
@@ -193,7 +193,9 @@ class ResultsWriter:
         mode = "w" if override_existing else "a"
         # Prevent newline issue on Windows, see GH issue #692
         self.file_handler = open(filename, f"{mode}t", newline="\n")
-        self.logger = csv.DictWriter(self.file_handler, fieldnames=("r", "l", "t", *extra_keys))
+        self.logger = csv.DictWriter(
+            self.file_handler, fieldnames=("r", "l", "t", *extra_keys)
+        )  # pytype: disable=wrong-arg-types
         if override_existing:
             self.file_handler.write(f"#{json.dumps(header)}\n")
             self.logger.writeheader()