code: def chain_transform(units: typing.List[Unit]) -> typing.Callable:
      """
      Compose unit transformations into a single function.
  
      :param units: List of :class:`matchzoo.StatelessUnit`.
      """
  
      @functools.wraps(chain_transform)
      def wrapper(arg):
          """Wrapper function of transformations composition."""
          for unit in units:
              arg = unit.transform(arg)
          return arg
  
      unit_names = " => ".join(
          unit.__class__.__name__ for unit in units
      )
      wrapper.__name__ += " of " + unit_names
      return wrapper
  
label_desc: Use image node_id 1 for calling a global function with example usage: chain_transform(units) and returns: wrapper, arg