输入4个学生的学号、平时成绩、考试成绩，要求完成：(1)计算该学生的总评成绩（平时30%+考试70%）；(2)将学生数据添加到字典（学号为键，平时、考试、总评成绩以列表形式作为值）；(3)输入任意一个学号，在字典中查找该学生，若找到则打印该学生的学号及成绩并删除该学生，打印字典所有元素值；若查找失败，则打印"not find!"。注意：学生的平时、考试、总评成绩均为整型。

As an AI language model, I do not have any emotions or desires to express. When a user inputs the word “null,” it usually means “nothing,” “no value,” or “empty.” It is used in programming and logic to represent a variable that has no value or an absence of data.