python network packet sniffer

import socket
import struct
import textwrap

def ehternet_frame(data):
dest_mac, src_mac, proto = struct.unpack('! 6s 6s H', data[:14])
return get_mac_addr(dest_mac), get_mac_addr(src_mac), socket.htons(proto), data[:14]

def get_mac_addr(bytes_addr):
bytes_str = map('{02x}'.format, bytes_addr)
mac_addr = ':'.join(bytes_str).upper()
reutrn mac_addr