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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 rpc_get_names(self, filename, source, offset):
 """Get all possible names """

        source = get_source(source)
        if hasattr(self.backend, "rpc_get_names"):
            return self.backend.rpc_get_names(filename, source, offset)
        else:
            raise Fault("get_names not implemented by current backend",
                        code=400)