变量由多选python更改

Question

我正在为多选游戏构建一个随机名称生成器，我需要知道如何使用户输入更改用于选项本身的变量。

这是我的代码：

main_name = 'William'

while True:
    if main_name == 'William':
        print ("Welcome to your life",main_name,". \n"
            "As you are an intelligent baby, you decide to call yourself,\n"
            " A. William \n B. Will \n C. Bill \n D. Billy")
        if input() in ['A','a','B','b','C','c','D','d']:
            break

    if input() == 'A' or 'a':
        main_name = 'William'
    if input() == 'B' or 'b':
        main_name = 'Will'
    if input() == 'C' or 'c':
        main_name = 'Bill'
    if input() == 'D' or 'd':
        main_name = 'Billy'

将感谢您的帮助:)谢谢