Django ManyToMany字段不接受正确的模型

# models.py
from django.db import models

class Student(models.Model):
    name = models.CharField(max_length=100)

class Course(models.Model):
    title = models.CharField(max_length=100)
    students = models.ManyToManyField(Student)

# models.py
from django.db import models

class Student(models.Model):
    name = models.CharField(max_length=100)

class Course(models.Model):
    title = models.CharField(max_length=100)
    students = models.ManyToManyField(Student, through='Enrollment')

class Enrollment(models.Model):
    student = models.ForeignKey(Student, on_delete=models.CASCADE)
    course = models.ForeignKey(Course, on_delete=models.CASCADE)
    enrollment_date = models.DateField()

# 删除旧的迁移文件
rm app_name/migrations/*.py

# 重新生成迁移文件
python manage.py makemigrations app_name

# 应用迁移
python manage.py migrate app_name