#!/usr/bin/env python

# from the Python Standard Library (2.5)
import hashlib, sys

if __name__ == '__main__':
    fobj = open(sys.argv[1], "r")
    hasher = hashlib.sha256()
    data = fobj.read(65536)
    while data:
        hasher.update(data)
        data = fobj.read(65536)
    print hasher.hexdigest()