code: def verify_no_new_dims(input_shapes, output_shape):
    
    all_input_dims = set(sum([s.dims for s in input_shapes], []))
    all_output_dims = set(output_shape.dims)
    if not all_output_dims.issubset(all_input_dims):
      raise ValueError(
          "No new dimensions allowed in output"
          " input_shapes = %s output_shape= %s"
          % ([s.dims for s in input_shapes], output_shape.dims))
docs: Verifies that all dimensions in the output are in at least one input.
  
    Args:
      input_shapes: a list of Shapes
      output_shape: a Shape
    Raises:
      ValueError: if there are new dimensions in the output.