wake-on-lan by python script

How to wake up your computer on the LAN?
the answer is just to send a Magic Packet to your computer on port 7 or 9.
However when your computer is down, it has no ip, so send it to the broadcast ip
the following python script implements the above idea.

import struct, socket

def wake_on_lan(ether_addr, inet_addr):
  addr_byte=ether_addr.split(':')
  hw_addr=struct.pack('BBBBBB',
    int(addr_byte[0],16),
    int(addr_byte[1],16),
    int(addr_byte[2],16),
    int(addr_byte[3],16),
    int(addr_byte[4],16),
    int(addr_byte[5],16))
  msg='\xff'*6+hw_addr*16
 
  s=socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
  s.setsockopt(socket.SOL_SOCKET, socket.SO_BROADCAST, 1)
  s.sendto(msg, (inet_addr,7))
  s.close()

wake_on_lan('00:E0:4C:E1:D9:CC', '192.168.1.255')

The code above is based on socket.SOCK_DGRAM to send UDP packet.
How to create a UDP packet based on raw socket in python?
the project dpkt does an excellent job.
the following example shows that:

import socket
from dpkt import ethernet,udp,ip
import dpkt
import struct
import string

iface = "eth1"
mac   = "00:0E:35:AB:9B:40"
inet  = "192.168.1.6"
debug = 0

def eth_aton(buffer):
    addr =''
    temp = string.split(buffer,':')
    buffer = string.join(temp,'')
    for i in range(0, len(buffer), 2):
        addr = ''.join([addr,struct.pack('B', int(buffer[i: i + 2], 16))],)
    return addr

def buildUdp():
    ether_addr='00:E0:4C:E1:D9:CD'
    addr_byte=ether_addr.split(':')
    hw_addr=struct.pack('BBBBBB',
       int(addr_byte[0],16),
       int(addr_byte[1],16),
       int(addr_byte[2],16),
       int(addr_byte[3],16),
       int(addr_byte[4],16),
       int(addr_byte[5],16))
    msg='xff'*6+hw_addr*16

    udp_p = udp.UDP()
    udp_p.sport = 0x8130
    udp_p.dport = 7
    udp_p.data = msg
    udp_p.ulen += len(udp_p.data)

    ip_p = ip.IP()
    ip_p.src = socket.inet_aton('192.168.1.6');
    ip_p.dst = socket.inet_aton('192.168.1.255');
    ip_p.off = 0x4000
    ip_p.data = udp_p
    ip_p.p = ip.IP_PROTO_UDP
    ip_p.len += len(udp_p)

    packet = ethernet.Ethernet()
    packet.src = eth_aton(mac)
    packet.dst = eth_aton('ff:ff:ff:ff:ff:ff')
    packet.data = ip_p
    packet.type = ethernet.ETH_TYPE_IP

    if debug: print dpkt.hexdump(str(packet))
    return packet

s = socket.socket(socket.PF_PACKET, socket.SOCK_RAW)
s.bind((iface,ethernet.ETH_TYPE_IP))
packet = buildUdp()
s.send(str(packet))