RuntimeError: dictionary changed size during iteration

[pavtiger]

Exception in thread Thread-1 (game_loop):
Traceback (most recent call last):
  File "/usr/lib/python3.10/threading.py", line 1016, in _bootstrap_inner
    self.run()
  File "/usr/lib/python3.10/threading.py", line 953, in run
    self._target(*self._args, **self._kwargs)
  File "/home/pavtiger/Docs/TRON_multiplayer/server.py", line 400, in game_loop
    TheGrid.update()
  File "/home/pavtiger/Docs/TRON_multiplayer/server.py", line 231, in update
    for bike_key in self.AllPlayers.keys():  # Iterate over all players
RuntimeError: dictionary changed size during iteration