Functions to convert IP addresses to decimals and back

ip_address.py

from socket import inet_pton, inet_ntop, AF_INET, AF_INET6
from struct import unpack, pack, error as struct_error


def ip2long(ip):
    '''Converts a user's IP address into an integer/long'''
    if '.' in ip:
        # ipv4
        return unpack('!i', inet_pton(AF_INET, ip))[0]
    else:
        # ipv6
        hi, lo = unpack('!QQ', inet_pton(AF_INET6, ip))
        return (hi << 64) | lo


def long2ip(ip_int):
    '''Converts a saved IP address back into an integer/long'''
    if ip_int < 4294967296:
        # ipv4
        return inet_ntop(AF_INET, pack('!i', ip_int))
    else:
        # ipv6
        return inet_ntop(AF_INET6, pack('!QQ', ip_int >> 64, ip_int & 0xffffffffffffffff))