在StudentEntity目录中定义函数

class Student:
    def __init__(self,no,name,age,contact):
        self.no=no
        self.name=name
        self.age=age
        self.contact=contact
    def __str__(self):
        return "{},{},{},{}".format(self.no,self.name,self.age,self.contact)
if __name__=="__main__":
    li=Student("2021","李四",20,123456)
    print(li)

然后在DataAccess定义函数

from StudentEntity import Student
def loadStudents():
    file=open("student.txt","r",encoding="utf-8")
    lines=file.readlines()
    students=[]
    for line in lines:
        a=line.split(",")
        students.append(Student(a[0],a[1],int(a[3].strip('\n'))))
    file.close()
    return students
def saveStudents(students):
    file=open("student.txt","w",encoding="utf-8")
    for x in students:
        file.write(str(x)+"\n")
    file.close()
if __name__=="__main__":
    a=loadStudents()
    print(a)
    a.append(Student("2024","赵六",21,20213011001))
    print(a)
    saveStudents(a)

最后，在main中，引用以上函数

import StudentEntity
from DataAccess import*
students=[]
def menu():
    print('-' * 40)
    print("欢迎使用学生通讯管理系统v2.0")
    print("[1] 增加学员信息")
    print("[2] 删除学员信息")
    print("[3] 打印学员信息")
    print("[4] 退出系统")
    print('-' * 40)
def add(students):
    no=input("请输入学员学号:")
    name=input("请输入学员姓名:")
    age=input("请输入学员年龄:")
    contact=input("请输入学员联系方式:")
    student=Student(no,name,age,contact)
    students.append(student)
    print("{}学员的信息已经成功添加！".format(student.name))
def remove(students):
    no=input("请输入要删除的学员学号:")
    for x in students:
        if x.no==no:
            print("学号为{}的{}同学被移除".format(x.no,x.name))
            students.remove(x)
            break
    else:
        print("没有找到该学员信息，请重试:")
if __name__=="__main__":
    students=loadStudents()
    while True:
        menu()
        op=int(input("请输入要进行的操作:"))
        if op==1:
            add(students)
        elif op==2:
            remove(students)
        elif op==3:
            for x in students:
                print(x)
        elif op==4:
            print("感谢使用本系统，期待下次光临！")
            break
        else:
            print("输入错误，请重新输入要操作的编号")
saveStudents(students)