用python类写1、输入并存储学生的信息 2、修改学生信息 3、删除学生信息 4、成绩排序 5、查找学生信息 6、进行测试

好的，以下是一个基本的实现：

class Student:
    def __init__(self, name, id, grade):
        self.name = name
        self.id = id
        self.grade = grade

class StudentDatabase:
    def __init__(self):
        self.student_list = []
        
    def add_student(self, name, id, grade):
        student = Student(name, id, grade)
        self.student_list.append(student)
        
    def modify_student(self, id, new_name, new_grade):
        for student in self.student_list:
            if student.id == id:
                student.name = new_name
                student.grade = new_grade
                break
        
    def delete_student(self, id):
        for student in self.student_list:
            if student.id == id:
                self.student_list.remove(student)
                break
        
    def sort_students(self):
        self.student_list.sort(key=lambda x: x.grade, reverse=True)
        
    def find_student(self, id):
        for student in self.student_list:
            if student.id == id:
                return student
        
    def run_tests(self):
        self.add_student("Alice", 1, 80)
        self.add_student("Bob", 2, 90)
        self.add_student("Charlie", 3, 85)
        
        self.modify_student(2, "Bobby", 95)
        
        self.delete_student(3)
        
        self.sort_students()
        
        print("Sorted student list:")
        for student in self.student_list:
            print(student.name, student.id, student.grade)
            
        print("Finding student with ID 1:")
        student = self.find_student(1)
        if student:
            print(student.name, student.id, student.grade)
        else:
            print("Student not found.")

我们定义了两个类，`Student` 表示学生信息，包括姓名、学号和成绩，`StudentDatabase` 表示学生信息的数据库，包括添加、修改、删除、排序和查找等操作。

我们可以通过 `StudentDatabase` 类的 `run_tests` 方法来测试实现的正确性。