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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_check_for_event( mask: int, k: Optional[Key], m: Optional[Mouse] ) -> int: """Check for and return an event. 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. .. deprecated:: 9.3 Use the :any:`tcod.event.get` function to check for events. """

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