docs: def ipv6(self, network=False):
          """Produce a random IPv6 address or network with a valid CIDR"""
          address = str(ip_address(self.generator.random.randint(
              2 ** IPV4LENGTH, (2 ** IPV6LENGTH) - 1)))
          if network:
              address += '/' + str(self.generator.random.randint(0, IPV6LENGTH))
              address = str(ip_network(address, strict=False))
          return address