所有对数据的访问与修改必须通过函数调用来完成。

All access and modifications to the data should be through function calls.

youdao

注意，函数只能作为不可变的序列访问这个列表—也就是说，尝试修改列表的内容会导致错误。

Note that the function can only access the list as an immutable sequence-that is, trying to modify the contents of the list results in an error.

youdao

在访问内部对象之前对内核代码进行修改，以调用一个代表实施函数的钩子，该实施函数实现安全策略。

Kernel code is modified prior to accessing internal objects to invoke a hook that represents an enforcement function, which implements the security policy.

youdao