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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def cleanup_handlers(event=None):
 """Remove handlers of a given `event`. If no event is informed, wipe out all events registered. Be careful!! This function is intended to help when writing tests and for debugging purposes. If you call it, all handlers associated to an event (or to all of them) will be disassociated. Which means that you'll have to reload all modules that teclare handlers. I'm sure you don't want it. """

    if event:
        if event in HANDLER_REGISTRY:
            del HANDLER_REGISTRY[event]
        if event in EXTERNAL_HANDLER_REGISTRY:
            del EXTERNAL_HANDLER_REGISTRY[event]
    else:
        HANDLER_REGISTRY.clear()
        EXTERNAL_HANDLER_REGISTRY.clear()