Update estimator.py

Author: nadiaya

src/sagemaker/rl/estimator.py

@@ -506,13 +506,7 @@ def default_metric_definitions(cls, toolkit):
             float_regex = "[-+]?[0-9]*[.]?[0-9]+([eE][-+]?[0-9]+)?"  # noqa: W605, E501
 
             return [
-                {
-                    "Name": "episode_reward_mean",
-                    "Regex": "episode_reward_mean: (%s)" % float_regex,
-                },
-                {
-                    "Name": "episode_reward_max",
-                    "Regex": "episode_reward_max: (%s)" % float_regex,
-                },
+                {"Name": "episode_reward_mean", "Regex": "episode_reward_mean: (%s)" % float_regex},
+                {"Name": "episode_reward_max", "Regex": "episode_reward_max: (%s)" % float_regex},
             ]
         raise ValueError("An unknown RLToolkit enum was passed in. toolkit: {}".format(toolkit))