带有嵌套函数和函数参数的程序输出

问：

给定以下代码

def alpha(num, proc):

    def beta(): print(num)

    if num == 1:
        alpha(2, beta)
    else:
        proc()

def gamma():
    pass

alpha(1, gamma)

我期望输出为 2，因为我的逻辑是：

   alpha(1, gamma)
=> alpha(2, beta)  # since num == 1
=> proc()          # since num != 1
=> beta()
=> print(2)        # since beta was a parameter alongside 2

但是，实际输出是 code is 1。谁能解释一下为什么会这样？