code: def listify_string(something):
      
      if isinstance(something, (str, six.text_type)):
          return [something]
      elif something is not None:
          return list(something)
      else:
          return list()
docs: Takes *something* and make it a list.
  
      *something* is either a list of strings or a string, in which case the
      function returns a list containing the string.
      If *something* is None, an empty list is returned.