send wake-on-land packets

import struct, socket

def WakeOnLan(mac):
    # Construct a six-byte hardware address
    hw_addr = struct.pack('BBBBBB', *(int(b, 16) for b in mac.split(':')))

    # Build the Wake-On-LAN "Magic Packet"...
    msg = '\xff' * 6 + hw_addr * 16

    # ...and send it to the broadcast address using UDP
    s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
    s.setsockopt(socket.SOL_SOCKET, socket.SO_BROADCAST, 1)
    s.sendto(msg, ('<broadcast>', 9))
    s.close()

if __name__=='__main__':
    from sys import argv
    try:
        WakeOnLan(argv[1])
    except (IndexError, ValueError):
        print "Bad arguments. Usage: %s ma:c:ad:dr:es:s" % argv[0]