在 Django 中使用邮箱地址或用户名登录用户

我正在try 创建一个auth后端，以允许我的用户使用他们的邮箱地址或他们在Django 1.6中的用户名使用自定义用户模型进行登录.当我使用用户名登录，但由于某种原因不能使用邮箱登录时，后端可以正常工作.我是不是忘了做什么事？

from django.conf import settings
from django.contrib.auth.models import User

class EmailOrUsernameModelBackend(object):
    """
    This is a ModelBacked that allows authentication with either a username or an email address.

    """
    def authenticate(self, username=None, password=None):
        if '@' in username:
            kwargs = {'email': username}
        else:
            kwargs = {'username': username}
        try:
            user = User.objects.get(**kwargs)
            if user.check_password(password):
                return user
        except User.DoesNotExist:
            return None

    def get_user(self, username):
        try:
            return User.objects.get(pk=username)
        except User.DoesNotExist:
            return None

编辑:按照建议，我已从ModelBackend继承并将其安装在我的设置中 我的设置里有这个 身份验证_后端=( ‘users.backends’， ‘django.contri.auth.backends.ModelBackend’， ) 我已经将后端更改为以下内容:

from django.conf import settings
from django.contrib.auth.models import User
from django.contrib.auth.backends import ModelBackend
class EmailOrUsernameModelBackend(ModelBackend):
    """
    This is a ModelBacked that allows authentication with either a username or an email address.

    """
    def authenticate(self, username=None, password=None):
        if '@' in username:
            kwargs = {'email': username}
        else:
            kwargs = {'username': username}
        try:
            user = User.objects.get(**kwargs)
            if user.check_password(password):
                return user
        except User.DoesNotExist:
            return None

    def get_user(self, username):
        try:
            return User.objects.get(pk=username)
        except User.DoesNotExist:
            return None

现在我得到一个Module "users" does not define a "backends" attribute/class错误.