load and save function for non-episodic replay buffers + carla improvements + network bug fixes

rl_coach/memories/non_episodic/experience_replay.py

@@ -15,6 +15,7 @@
 #
 
 from typing import List, Tuple, Union, Dict, Any
+import pickle
 
 import numpy as np
 
@@ -218,3 +219,21 @@ class ExperienceReplay(Memory):
         self.reader_writer_lock.release_writing()
 
         return mean
+
+    def save(self, file_path: str) -> None:
+        """
+        Save the replay buffer contents to a pickle file
+        :param file_path: the path to the file that will be used to store the pickled transitions
+        """
+        with open(file_path, 'wb') as file:
+            pickle.dump(self.transitions, file)
+
+    def load(self, file_path: str) -> None:
+        """
+        Restore the replay buffer contents from a pickle file.
+        The pickle file is assumed to include a list of transitions.
+        :param file_path: The path to a pickle file to restore
+        """
+        with open(file_path, 'rb') as file:
+            self.transitions = pickle.load(file)
+        self._num_transitions = len(self.transitions)