#!/usr/bin/env python3
import hashlib
from concurrent.futures import ThreadPoolExecutor, as_completed

def matches(word, target, algo):
    h = hashlib.new(algo); h.update(word.encode())
    return h.hexdigest() == target.lower()

def crack(target, wordlist, algo="sha256", workers=8):
    with open(wordlist, encoding="utf-8", errors="ignore") as f:
        words = [w.strip() for w in f if w.strip()]
    with ThreadPoolExecutor(max_workers=workers) as ex:
        futs = {ex.submit(matches, w, target, algo): w for w in words}
        for fut in as_completed(futs):
            if fut.result():
                return futs[fut]
    return None

if __name__ == "__main__":
    print(crack("<target-hash>", "/usr/share/wordlists/rockyou.txt", "md5"))