code: def get_tensor_mtf_dimension_names(self, tensor_name):
      
      tensor = self._name_to_tensor(tensor_name)
      if isinstance(tensor, mtf.Tensor):
        return tensor.shape.dimension_names
      else:  # tf.Tensor
        return []
docs: The Mesh TensorFlow dimensions associated with a tensor.
  
      Args:
        tensor_name: a string, name of a tensor in the graph.
  
      Returns:
        a [string], the names of Mesh TensorFlow dimensions.