docs: def encode(cls, value):
          """
          take a list of strings and turn it into utf-8 byte-string
  
          :param value:
          :return:
          """
          coerced = unicode(value)
          if coerced == value and cls.PATTERN.match(coerced):
              return coerced.encode(cls._encoding)
  
          raise InvalidValue('not ascii')