Exception in thread Thread-1: Traceback (most recent call last): File "/usr/lib/python2.7/threading.py", line 551, in __bootstrap_inner self.run() File "/usr/lib/python2.7/threading.py", line 504, in run self.__target(*self.__args, **self.__kwargs) File "./server.py", line 103, in runTicks_players for player in PLAYERS: RuntimeError: Set changed size during iteration

Created tmp_player_list where players are added upon login. Tickthread now handles adding players to main ticking list.