AUTHENTICATION_BACKENDS = ('login_app.backends.LoginBackend',
                        'django.contrib.auth.backends.ModelBackend')

# Password validation
# https://docs.djangoproject.com/en/1.9/ref/settings/#auth-password-validators

AUTH_PASSWORD_VALIDATORS = [
    {
        'NAME': 'django.contrib.auth.password_validation.UserAttributeSimilarityValidator',
    },
    {
        'NAME': 'django.contrib.auth.password_validation.MinimumLengthValidator',
    },
    {
        'NAME': 'django.contrib.auth.password_validation.CommonPasswordValidator',
    },
    {
        'NAME': 'django.contrib.auth.password_validation.NumericPasswordValidator',
    },
]

def authenticate(self, email=None, password=None):
    try:
        user = User.objects.get(email=email)
        if password == user.password:
            return user
        else:
            return None
    except User.DoesNotExist:
        return None