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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 cancel(self, force=False):
 """Cancel this job. Args: force (bool, optional):
 Forcefully cancel this job. Returns: bool: True if the job was cancelled, otherwise False if an error occurred. """

        return self.rest_client._sc._delegator._cancel_job(self, force)