code: def ipv4_private(self, network=False, address_class=None):
          
          # compute private networks from given class
          supernet = _IPv4Constants._network_classes[
              address_class or self.ipv4_network_class()
          ]
  
          private_networks = [
              subnet for subnet in _IPv4Constants._private_networks
              if subnet.overlaps(supernet)
          ]
  
          # exclude special networks
          private_networks = self._exclude_ipv4_networks(
              private_networks,
              _IPv4Constants._excluded_networks,
          )
  
          # choose random private network from the list
          private_network = self.generator.random.choice(private_networks)
  
          return self._random_ipv4_address_from_subnet(private_network, network)
docs: Returns a private IPv4.
  
          :param network: Network address
          :param address_class: IPv4 address class (a, b, or c)
          :returns: Private IPv4