def authenticate(self, username=None, password=None):
        try:
            user = User.objects.get(username__iexact=username)
            if user.check_password(password):
                return user
        except User.DoesNotExist:
            return None
Mark the current version of the review branch as 'bad land'.
dataset/ETHPy150Open kobotoolbox/kobocat/onadata/apps/main/backends.py/ModelBackend.authenticate--crossover with--dataset/ETHPy150Open bloomberg/phabricator-tools/py/abd/abdt_branch.py/Branch.mark_bad_land