code: def check_missing(self, args):
          
          return [opt.name for opt in self
                  if (opt.name not in args) and (opt.default is None)]
docs: Returns the names of all options that are required but were not specified.
  
          All options that don't have a default value are required in order to run the
          workflow.
  
          Args:
              args (dict): A dictionary of the provided arguments that is checked for
                           missing options.
  
          Returns:
              list: A list with the names of the options that are missing from the
                    provided arguments.