import hashlib


def get_file_sha1(path):
    """Helper function to compute SHA1 of given ``path``"""
    hashval = hashlib.sha1()
    with open(path, 'rb') as inputfile:
        while True:
            chunk = inputfile.read(80 * 1024 * 1024)
            if len(chunk) == 0:
                break
            hashval.update(chunk)
    return str(hashval.hexdigest()).lower()