#!/usr/bin/env python3

from hashlib import sha1
from itertools import count

def hash_it(gen):
    for i in gen:
        input_string = "Netzwerksicherheit_{}".format(i).encode()
        hash_code = sha1(input_string).hexdigest()
        yield (input_string, hash_code)

if __name__ == "__main__":
    g = hash_it(count())
    last = next(g)
    while not last[1].startswith("0000"):
        last = next(g)
    print(last)