Quick fix for fast execution stream throwing an exception upon subscription

[kolya5544]

No description provided.

[kolya5544]

fix for:

def handle_message(message):
    print(message)


wsp.fast_execution_stream(callback=handle_message, categorised_topic="spot")

resulting in:

  File "D:\Programs\Develop\Python\Python310\lib\site-packages\pybit\unified_trading.py", line 155, in fast_execution_stream      
    self.subscribe(topic, callback)
  File "D:\Programs\Develop\Python\Python310\lib\site-packages\pybit\_websocket_stream.py", line 346, in subscribe
    subscription_args = prepare_subscription_args(symbol)
  File "D:\Programs\Develop\Python\Python310\lib\site-packages\pybit\_websocket_stream.py", line 339, in prepare_subscription_args
    for single_symbol in list_of_symbols:
TypeError: 'bool' object is not iterable