Simple python script to look for 401s using requests. Explained for educational audiences.

401.py

import sys
import requests

# define an array to hold our hosts
hosts = []

# open the file as the variable f
# this will close the file as soon we're done
with open(sys.argv[1]) as f:
  # this is called a list comprehension. it's neat way to loop over 
  # something and put the results into a list
  hosts = [x.rstrip() for x in f.readlines()]

for host in hosts:
  # python methods will throw execeptions when something bad happens
  # you have to catch them with these try/except blocks
  try:
    r = requests.get('http://{0}/'.format(host), timeout=0.5)
    print r.status_code
    if r.status_code == 401:
      print host
  # if the request timesout it throws a 'requests.exceptions.Timeout'    
  except requests.exceptions.Timeout:
    # pass means keep moving on, nothing to see here
    pass