密码学编程 _换位加密法

import pyperclip
def main():
    myMessage='Commen sense is not so common.'
    myKey=8
    ciphertext=encryptMessage(myKey,myMessage)
    print(ciphertext+'|')
    pyperclip.copy(ciphertext)
def encryptMessage(key,message):
    ciphertext=['']*key
    for col in range(key):
        pointer=col
        while pointer<len(message):
            ciphertext[col]+=message[pointer]
            pointer+=key
    return ''.join(ciphertext)
if __name__== '__main__':
    main()

注意：倒数第二行，name和main前后都是两条下划线，而不是一条。