'Generate the information required to create an ISBN-10 or
ISBN-13.'

def _body(self):

    ean = self.random_element(RULES.keys())
    reg_group = self.random_element(RULES[ean].keys())
    reg_pub_len = (((ISBN.MAX_LENGTH - len(ean)) - len(reg_group)) - 1)
    reg_pub = self.numerify((u'#' * reg_pub_len))
    rules = RULES[ean][reg_group]
    (registrant, publication) = self._registrant_publication(reg_pub, rules)
    return [ean, reg_group, registrant, publication]
