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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:
 async def stop(self):
 """Stop the current task process. Starts with SIGTERM, gives the process 1 second to terminate, then kills it """

        # negate pid so that signals apply to process group
        pgid = -self.process.pid
        try:
            os.kill(pgid, signal.SIGTERM)
            await asyncio.sleep(1)
            os.kill(pgid, signal.SIGKILL)
        except (OSError, ProcessLookupError):
            return