Python DNS Packet Sniffer

#! /usr/bin/python

from scapy.all import *
import sys

try:
    interface = raw_input("[*] Enter Desired Interface: ")
except KeyboardInterrupt:
    print "[*] User Requested Shutdown..."
    print "[*] Exiting..."
    sys.exit(1)

def querysniff(pkt):
    if IP in pkt:
        ip_src = pkt[IP].src
        ip_dst = pkt[IP].dst
        if pkt.haslayer(DNS) and pkt.getlayer(DNS).qr == 0:
            print str(ip_src) + " -> " + str(ip_dst) + " : " + "(" + pkt.getlayer(DNS).qd.qname + ")"

sniff(iface = interface,filter = "port 53", prn = querysniff, store = 0)
print "\n[*] Shutting Down..."