code: def pad(x, paddings, dim_name, name=None):
    
    return PadOperation(
        x, paddings, dim_name, name=name).outputs[0]
docs: Slice operation.
  
    Args:
      x: a list of Tensors
      paddings: list of integers of size 2, padding size before and after for dim.
      dim_name: string, name for the padding dim
      name: an optional string
    Returns:
      a Tensor with shape extended by output_shape for the last axis.