帮我写一个考试管理系统

好，考试管理系统一般包括以下功能：

1. 学生管理：添加、修改、删除学生信息。

2. 教师管理：添加、修改、删除教师信息。

3. 课程管理：添加、修改、删除课程信息。

4. 考试安排：安排考试时间、地点、考试科目等信息。

5. 成绩管理：录入、修改、查询学生成绩信息。

6. 统计分析：统计各科成绩、排名等信息。

下面是一个简单的考试管理系统的代码示例：

class Student:
    def __init__(self, name, age, sex, id):
        self.name = name
        self.age = age
        self.sex = sex
        self.id = id
        
class Teacher:
    def __init__(self, name, age, sex, id, subject):
        self.name = name
        self.age = age
        self.sex = sex
        self.id = id
        self.subject = subject
        
class Course:
    def __init__(self, name, teacher, time, place):
        self.name = name
        self.teacher = teacher
        self.time = time
        self.place = place
        
class Exam:
    def __init__(self, course, time, place):
        self.course = course
        self.time = time
        self.place = place
        
class Grade:
    def __init__(self, student, course, score):
        self.student = student
        self.course = course
        self.score = score
        
class ExamSystem:
    def __init__(self):
        self.students = []
        self.teachers = []
        self.courses = []
        self.exams = []
        self.grades = []
        
    def add_student(self, name, age, sex, id):
        s = Student(name, age, sex, id)
        self.students.append(s)
        
    def add_teacher(self, name, age, sex, id, subject):
        t = Teacher(name, age, sex, id, subject)
        self.teachers.append(t)
        
    def add_course(self, name, teacher, time, place):
        c = Course(name, teacher, time, place)
        self.courses.append(c)
        
    def add_exam(self, course, time, place):
        e = Exam(course, time, place)
        self.exams.append(e)
        
    def add_grade(self, student, course, score):
        g = Grade(student, course, score)
        self.grades.append(g)
        
    def get_student_info(self, id):
        for s in self.students:
            if s.id == id:
                return s
        return None
    
    def get_teacher_info(self, id):
        for t in self.teachers:
            if t.id == id:
                return t
        return None
    
    def get_course_info(self, name):
        for c in self.courses:
            if c.name == name:
                return c
        return None
    
    def get_exam_info(self, course):
        for e in self.exams:
            if e.course == course:
                return e
        return None
    
    def get_grade_info(self, student):
        student_grades = []
        for g in self.grades:
            if g.student == student:
                student_grades.append(g)
        return student_grades
    
    def get_course_grades(self, course):
        course_grades = []
        for g in self.grades:
            if g.course == course:
                course_grades.append(g)
        return course_grades
        

这个考试管理系统包含了添加学生、教师、课程、考试信息，录入成绩，查询学生、教师、课程、考试、成绩信息等功能。你可以根据自己的需求进行修改和扩展。