Generate VM MAC addresses from last 3 of IP range

ip2mac.py

#!/usr/bin/env python
import sys

# turn IP address string into array of int
def parseip(ipstr):
    array = ipstr.split('.')
    return [int(x) for x in array]

# append last 3 of IP to static MAC vendor ID and return printable string
def ip2mac(ip):
    mac = [ 0x00, 0x16, 0x3e]
    mac += ip[1:]
    return ':'.join(map(lambda x: "%02x" % x, mac))

if __name__ == "__main__":
    if (len(sys.argv) > 1):
        ip = sys.argv[1]
    else:
        ip = "192.168.72.1"

    print (ip2mac(parseip(ip)))