gistfile1.py

#!/usr/bin/env python
import sys
# default dns query timeout is 5 seconds
retrans = 5
# give the user a chance to override it by passing an argument
if (len(sys.argv) == 2):
        retrans = int(sys.argv[1])

# 3 dummy IP addresses
nameservers = ["1.1.1.1", "2.2.2.2", "3.3.3.3"]
# nscount is the count of nameservers
nscount = len(nameservers)
# lets loop over them all and replicate the logic found in res_send.c
for nameserver in nameservers:
    ns = nameservers.index(nameserver)

    seconds = ( retrans << ns )
    if (ns > 0):
        seconds = seconds / nscount
    if (seconds <= 0):
        seconds = 1
    # and for visibility we print it out
    print "Nameserver # {} has timeout {}".format(ns,seconds)