gistfile1.txt

-> % python silly_ip.py                         
{74: {125: {232: {211: 1, 20174: 1}}}, 79: {115: {74: {141: 1}}}}

silly_ip.py

#!/usr/bin/env python
# -*- coding: utf8 -*-
import sys

dummy_data = [
    '74.125.232.201'
    '74.125.232.206',
    '74.125.232.211',
    '79.115.74.141'
]


def main(argv):
    root = {}

    for raw_ip in dummy_data:
        ip = [int(i) for i in raw_ip.split('.')]
        tmp = root.setdefault(ip[0], {})
        tmp = tmp.setdefault(ip[1], {})
        tmp = tmp.setdefault(ip[2], {})
        tmp[ip[3]] = tmp.get(ip[3], 0) + 1

    print root

    return 0


if __name__ == '__main__':
    sys.exit(main(sys.argv))