def is_mutable_by(self, user):
        return user.has_perm('reviews.change_default_reviewer',
                             self.local_site)
Tests assignment using the field's save method and deletion using
dataset/ETHPy150Open reviewboard/reviewboard/reviewboard/reviews/models/default_reviewer.py/DefaultReviewer.is_mutable_by--crossover with--dataset/ETHPy150Open AppScale/appscale/AppServer/lib/django-1.2/tests/regressiontests/model_fields/imagefield.py/ImageFieldTwoDimensionsTests.test_field_save_and_delete_methods