models.py里的数据库定义如下：

from django.db import models# Create your models here.class Teachers(models.Model):    name = models.CharField(max_length=32)class Classes(models.Model):    title = models.CharField(max_length=32)    a = models.ManyToManyField(Teachers)class Students(models.Model):    username = models.CharField(max_length=32)    age = models.IntegerField()    gender = models.BooleanField()    cs = models.ForeignKey(Classes, on_delete=models.CASCADE)

tests.py里的内容如下，注意红色部分，是比较麻烦一点的，要构建好相关的orm语句及使用assertIn之类的来测试。

from django.test import TestCasefrom .models import Students, Teachers, Classes# Create your tests here.class ModelTest(TestCase):    def setUp(self):        t1 = Teachers.objects.create(name="Mrs. Chane")        t2 = Teachers.objects.create(name="Mss. Fang")        Teachers.objects.create(name="ABC")        c1 = Classes(title="123")        c1.save()        c1.a.add(t1)        c1.a.add(t2)        c1.save()        Students.objects.create(username="bb",                                age=23,                                gender=True,                                cs=c1)    def test_teacher_models(self):        result = Teachers.objects.get(name="Mrs. Chane")        self.assertEqual(result.name, "Mrs. Chane")    def test_class_models(self):        t1 = Teachers.objects.get(name="Mrs. Chane")        t2 = Teachers.objects.get(name="Mss. Fang")        t3 = Teachers.objects.get(name="ABC")        result = Classes.objects.get(title="123")        self.assertEqual(result.title, "123")        self.assertIn(t1, result.a.all())        self.assertIn(t2, result.a.all())        self.assertNotIn(t3, result.a.all())    def test_student_models(self):        result = Students.objects.get(username="bb")        self.assertEqual(result.age, 23)        c1 = Classes.objects.get(title="123")        self.assertEqual(result.cs, c1)        self.assertEqual(result.gender, True)