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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 execute(self, command, *args, **kwargs):
 """Execute sentinel command."""

        # TODO: choose pool
        #   kwargs can be used to control which sentinel to use
        if self.closed:
            raise PoolClosedError("Sentinel pool is closed")
        for pool in self._pools:
            return pool.execute(command, *args, **kwargs)