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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 get_op_or_tensor_by_name(name):
 """ Get either tf.Operation of tf.Tensor from names. Args: name (list[str] or str):
 names of operations or tensors. Raises: KeyError, if the name doesn't exist """

    G = tfv1.get_default_graph()

    def f(n):
        if len(n) >= 3 and n[-2] == ':':
            return G.get_tensor_by_name(n)
        else:
            return G.get_operation_by_name(n)

    if not isinstance(name, list):
        return f(name)
    else:
        return list(map(f, name))