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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 kill(self, exit_code: Any = None):
 """ Stops the behaviour Args: exit_code (object, optional):
 the exit code of the behaviour (Default value = None) """

        self._force_kill.set()
        if exit_code is not None:
            self._exit_code = exit_code
        logger.info("Killing behavior {0} with exit code: {1}".format(self, exit_code))