Django You have multiple authentication backends - solution

ValueError: You have multiple authentication backends configured and therefore must provide the 'backend' argument or set the 'backend' attribute on the user.

a short solution to fix this error and also i am going to let you know ' what causing this error !

basically this error is triggered by multiple authentication backend which you have set or created for your custom authentication backend

as an example of your authentication backend....with your custom authentication backend

AUTHENTICATION_BACKENDS = (
    'games.backend.EmailorUsernameAuthBackend',

    'django.contrib.auth.backends.RemoteUserBackend',
    'django.contrib.auth.backends.ModelBackend',
)

 in your function in which you are using authenticate() and login() method's 
 this error say's add backend argument or set 'backend' attribute on user.

 just do this example:

user = authenticate(request,username=username, password= password)
login(request, user, backend='games.backend.EmailorUsernameAuthBackend')

detail : backend=' yourappname.backendlocationinappdirectory.backendfilename'

i hope this small explanation helps you out but make sure to add custom backend in your login() function as an argument.
let me know what you did in comments below.