pepperino

key = open('sub_key.txt', 'r')
cipher = open('sub_ciphertext.txt', 'r')
plainText = open('sub_plaintext.txt', 'w')

counter = 0
keylist = []
for line in key:
	for char in line:
		keylist.append(char)

for cipherLine in cipher:
	for cipherChar in cipherLine:
		if not (cipherChar in keylist):
			plainText.write(cipherChar)
		else:
			plainChar = 65 + keylist.index(cipherChar)
			plainText.write(chr(plainChar))