from hashlib import sha256
from itertools import cycle
import base64

def crypt(msg: bytes, key: str) -> bytes:
	key_h = sha256()
	key_h.update(key.encode('utf8'))
	key = key_h.digest()

	return bytes(p ^ k for (p, k) in zip(msg, cycle(key)))

def encrypt(msg: str, key: str) -> str:
	return base64.b64encode(crypt(bytes(msg, 'utf8'), key)).decode('utf8')

def decrypt(msg: str, key: str) -> str:
	return crypt(base64.b64decode(msg), key).decode('utf8')