Django仅允许非关系和外键

Question

我试图在这里创建一个脚本，查看我的员工表列表，分析员工的电子邮件地址，并将其与系统中的登录名进行比较，以将其分配给他们的教室，但我的脚本不断崩溃

目标是什么？ 我们的目标是我有一个叫做分区的表格，分区就是教室。每个教室都有一位老师。但是，为了让老师看到分配给他们的教室，我会通过用户的登录名（即他们的电子邮件地址）将其链接起来。然而，尽管打印语句中的逻辑对查询有效，但无法更新多对多字段。这是我的密码

FUNCTION

def AssignLoginToSection():
  users = User.objects.all()
  for user_email in users:
    email = user_email.email 
    print('Getting Email addresses in system.')
    if Section.objects.filter(staffpsid__email = email):
      section = Section.objects.filter(staffpsid__email = email)
      print("Found Matching Login Name.")
      print('The following sections were found with this users email.', section)
      Section.objects.filter(staffpsid__email = email).update(teacher_username= email)
      print('Added user login name to section.')
    else:
     print("No matching login name.")
  return("Done")   

MODELS

# Section Information Stored
class Section(models.Model):
    sectionpsid= models.CharField(primary_key = True, default = "", max_length = 50)
    schoolpsid = models.ForeignKey(School,on_delete = models.CASCADE, default = "" ,)
    coursepsid = models.ForeignKey(Course,on_delete = models.CASCADE, default = "" ,) 
    termpsid = models.ForeignKey(Term,on_delete = models.CASCADE, default = "" ,) 
    section_number = models.CharField(default = "", max_length = 50)
    expression = models.CharField(default = "", max_length = 50)
    external_expression= models.CharField(default = "", max_length = 50)
    staffpsid = models.ForeignKey(Staff,on_delete = models.PROTECT, default = "" ,) 
    gradebooktype = models.CharField(default = "", max_length = 50)
    teacher_username = models.ManyToManyField(User)
 
# Staff Information Stored
class Staff(models.Model):
    staffpsid= models.CharField(primary_key = True, default = "", max_length = 50)
    first_name = models.CharField(max_length = 50, default = "")
    last_name = models.CharField(max_length = 50, default = "")
    staff_name = models.CharField(max_length = 50, default = "")
    email = models.EmailField(default = "", unique = True)
    staff_cell = models.CharField(max_length = 12, default = "")
    users_dcid = models.CharField(max_length = 5, default = "")   

    

我得到的错误是无法更新模型字段<；django.db.models.fields.related.ManyToManyField:teacher\u username>；（仅允许使用非关系键和外键）

Answer 1

ManyToManyField使用添加或删除方法

而不是：

Section.objects.filter(staffpsid__email = email).update(teacher_username= email)

使用：

section.teacher_username.add(user_email.id)