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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 set_keyspace(self, keyspace):
 """ switch all connections to another keyspace """

        self.keyspace = keyspace
        dfrds = []
        for p in self._protos:
            dfrds.append(p.submitRequest(ManagedThriftRequest(
                'set_keyspace', keyspace)))
        return defer.gatherResults(dfrds)