Что я делаю, как он говорит синтаксическая ошибка

Question

У меня есть код, который постоянно говорит синтаксическая ошибка, пожалуйста, помогите.

count = 0
output = []
encoded = []
keylist = []
stringlist = []
alphabet = [ "a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m", "n", "o", "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z" ]
print(" what would you like to do: ")
print("options: ")
print("1 - encode")
print("2 - decode")
print()
while 1==1:
    option = int(input("option = " ))
    key = input("please enter the key you would like to use: ")
    string = input("please enter the string you would like to encode/decode: ")
    string = string.replace(' ', '')
    keylenth = len(key)
    stringlenth = len(string)
    overlap = stringlenth % keylenth
    leftovers = key[:overlap]
    random = stringlenth-overlap
    random = stringlenth/keylenth
    key = (int(random)*key)+leftovers

    for i in string:
        number = alphabet.index(i.upper())
        stringlist.append(number)

    i = 0

    if(option == 1):
        while count < stringlenth:
            encoded.append((stringlist[i]+keylist[i])%26
            count += 1
            i += 1
        for n in encoded:
            output.appened(alphabet[n])

    string = ''.join(output)
    print()
    print('output::')
    print()
    print(string)
    print()
    print()

Answer 1

Я вижу строку с отсутствующей закрывающей скобкой - это может быть причиной:

encoded.append ((список строк [i]+ список ключей [i])% 26 )