code: def register(cls):
      """
      Register a given module class.
      Args:
          cls (type): Module class to be registered.
      Returns: cls
      """
      if cls.__name__ in global_config:
          raise ValueError(
              "Module class already registered: {}".format(cls.__name__)
          )
      global_config[cls.__name__] = cls
      return cls
  
label_desc: Use image node_id 1 for calling a global function with example usage: register(cls) and returns: cls