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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 sys_wait_for_event( mask: int, k: Optional[Key], m: Optional[Mouse], flush: bool ) -> int: """Wait for an event then return. If flush is True then the buffer will be cleared before waiting. Otherwise each available event will be returned in the order they're recieved. Args: mask (int):
 :any:`Event types` to wait for. k (Optional[Key]):
 A tcod.Key instance which might be updated with an event. Can be None. m (Optional[Mouse]):
 A tcod.Mouse instance which might be updated with an event. Can be None. flush (bool):
 Clear the event buffer before waiting. .. deprecated:: 9.3 Use the :any:`tcod.event.wait` function to wait for events. """

    return int(
        lib.TCOD_sys_wait_for_event(
            mask,
            k.key_p if k else ffi.NULL,
            m.mouse_p if m else ffi.NULL,
            flush,
        )
    )