Solution for Coursera Cryptography 1 course Week 3 programming assignment

hash.py

from hashlib import sha256
from sys import argv

with open(argv[1], "rb") as f:
    blocks = []
    
    block = f.read(1024)
    while block:
        blocks.append(block)
        block = f.read(1024)

    h = sha256(blocks[-1])
    for block in reversed(blocks[:-1]):
        h = sha256(block + h.digest())

    print(h.hexdigest())