Login with Email – Django

You should write a custom authentication backend.

from django.contrib.auth import get_user_model
from django.contrib.auth.backends import ModelBackend

class EmailBackend(ModelBackend):
    def authenticate(self, request, username=None, password=None, **kwargs):
        UserModel = get_user_model()
            user = UserModel.objects.get(email=username)
        except UserModel.DoesNotExist:
            return None
            if user.check_password(password):
                return user
        return None

Then, set that backend as your auth backend in your settings:

AUTHENTICATION_BACKENDS = ['path.to.auth.module.EmailBackend']