code: def netmask_long(self):
          
          if self.version() == 4:
              return (MAX_IPV4 >> (32 - self.mask)) << (32 - self.mask)
          else:
              return (MAX_IPV6 >> (128 - self.mask)) << (128 - self.mask)
docs: Network netmask derived from subnet size, as long.
  
          >>> localnet = Network('127.0.0.1/8')
          >>> print(localnet.netmask_long())
          4278190080