Listing 1. checkIP.py

# Programmer: Mihalis Tsoukalos
# Date: Tuesday 28 October 2014

import socket
import sys
import re

def valid_ip(address):
    try:
        socket.inet_aton(address)
        return True
    except:
        return False

# Counters for the IPs
total = 0
valid = 0
invalid = 0

# Read the file from stdin, line by line
for line in sys.stdin:
        line = line.rstrip('\n')
        if valid_ip(line):
            valid = valid + 1
            # print "The IP is valid!"
        else:
            # print "The IP is not valid!"
            invalid = invalid + 1
        total = total + 1

# Present the total number of IPs checked
print "Total number of IPs checked:", total
print "Valid IPs found:", valid
print "Invalid IPs found:", invalid