code: def _validate_str_list(arg):
      '''
      ensure ``arg`` is a list of strings
      '''
      if isinstance(arg, six.binary_type):
          ret = [salt.utils.stringutils.to_unicode(arg)]
      elif isinstance(arg, six.string_types):
          ret = [arg]
      elif isinstance(arg, Iterable) and not isinstance(arg, Mapping):
          ret = []
          for item in arg:
              if isinstance(item, six.string_types):
                  ret.append(item)
              else:
                  ret.append(six.text_type(item))
      else:
          ret = [six.text_type(arg)]
      return ref _validate_str_list(arg):
      '''
      ensure ``arg`` is a list of strings
      '''
      if isinstance(arg, six.binary_type):
          ret = [salt.utils.stringutils.to_unicode(arg)]
      elif isinstance(arg, six.string_types):
          ret = [arg]
      elif isinstance(arg, Iterable) and not isinstance(arg, Mapping):
          ret = []
          for item in arg:
              if isinstance(item, six.string_types):
                  ret.append(item)
              else:
                  ret.append(six.text_type(item))
      else:
          ret = [six.text_type(arg)]
      return ret
docs: ensure ``arg`` is a list of strings