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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 _name_to_tensor(self, tensor_name):
 """The tensor with the given name. Args: tensor_name: a string, name of a tensor in the graph. Returns: a tf.Tensor or mtf.Tensor """

    id1, id2 = self._tensor_name_to_ids[tensor_name]
    return self._operations[id1].outputs[id2]