'Given a request that specifies an oauth `client_id`, return the adapter
for the appropriate OAuth handling library.  If the client_id is found
in a django-oauth-toolkit (DOT) Application, use the DOT adapter,
otherwise use the django-oauth2-provider (DOP) adapter, and allow the
calls to fail normally if the client does not exist.'

def select_backend(self, request):

    return self.get_adapter(request).backend
