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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 login(self, credentials):
 """ authenticate all connections """

        dfrds = []
        for p in self._protos:
            dfrds.append(p.submitRequest(ManagedThriftRequest('login',
                    ttypes.AuthenticationRequest(credentials=credentials))))
        return defer.gatherResults(dfrds)