code: def update_cached_fields(*args):
      
      for a in args:
          if a is not None:
              if hasattr(a, '__iter__'):
                  for e in a:
                      e.update_cached_fields()
              else:
                  a.update_cached_fields()
docs: Calls update_cached_fields() for each object passed in as argument.
      Supports also iterable objects by checking __iter__ attribute.
      :param args: List of objects
      :return: None