Merge pull request octo-models#140 from rail-berkeley/easy_dataset_st…

…aitstics

Convenience function to load dataset stats

orca/utils/pretrained_utils.py

@@ -137,9 +137,21 @@ def sample_actions(self, observations, tasks, pad_mask=None, train=False, **kwar
             **kwargs,
         )
 
-    @classmethod
+    @staticmethod
+    def load_dataset_statistics(
+        checkpoint_path: str, dataset_name: Optional[str] = None
+    ):
+        if dataset_name is not None:
+            statistics_path = f"dataset_statistics_{dataset_name}.json"
+        else:
+            statistics_path = "dataset_statistics.json"
+        statistics_path = tf.io.gfile.join(checkpoint_path, statistics_path)
+        with tf.io.gfile.GFile(statistics_path, "r") as f:
+            statistics = json.load(f)
+        return statistics
+
+    @staticmethod
     def load_config(
-        cls,
         checkpoint_path: str,
     ):
         config_path = tf.io.gfile.join(checkpoint_path, "config.json")