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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 command(self, rs_id, command, *args):
 """Call a ReplicaSet method."""

        rs = self._storage[rs_id]
        try:
            return getattr(rs, command)(*args)
        except AttributeError:
            raise ValueError("Cannot issue the command %r to ReplicaSet %s"
                             % (command, rs_id))