Ошибка "list index out of range", хотя вроде все правильно.

import string
import random
key = [ ]
alp_m = [ ]
alp = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZабвгдеёжзийклмнопрстуфхцчшщъыьэюяАБВГДЕЁЖЗИЙКЛМНОПРСТУФХЦЧШЩЪЫЬЭЮЯ"
def dic():
for i in alp:
alp_m.append(i)
return alp_m
def keygen():
for i in range(len(alp)):
key.append(i)
key[i] = i
random.shuffle(key)
key2 = key
print(str(" ".join(map(str, key2)) + " - ключ"))
return key2
def cyphergen(key2):
alp_c = [ ]
for i in range(len(alp)):
alp_c.append(i)
alp_c[i] = alp_m[int(key2[i])]
print(alp_c)
return(alp_c)
cyphergen(keygen())

Код

import string

import random

key = [ ]

alp_m = [ ]

alp = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZабвгдеёжзийклмнопрстуфхцчшщъыьэюяАБВГДЕЁЖЗИЙКЛМНОПРСТУФХЦЧШЩЪЫЬЭЮЯ"

def dic():

    for i in alp:

        alp_m.append(i)

    return alp_m

def keygen():

    for i in range(len(alp)):

        key.append(i)

        key[i] = i

    random.shuffle(key)

    key2 = key

    print(str(" ".join(map(str, key2)) + " - ключ"))

    return key2

def cyphergen(key2):

    alp_c = [ ]

    for i in range(len(alp)):

        alp_c.append(i)

        alp_c[i] = alp_m[int(key2[i])]

        print(alp_c)

    return(alp_c)

cyphergen(keygen())

в строке alp_c = alp_m[int(key2)] вылезает ошибка "list index out of range"