import hashlib

def hex(data:bytes)->str:
    return hashlib.sha256(data).hexdigest()

def double(data:bytes)->str:
    first = hashlib.sha256(data).digest()
    second = hashlib.sha256(first).hexdigest()
    return second

if __name__=="__main__":
    data = b"The quick brown fox jump over the river"
    print("first hash : ", hex(data))
    print("second hash : ", double(data))