def gradient(self, theta):
        pass
Ensure that posts are being sorted properly by date/time.
dataset/ETHPy150Open automl/RoBO/robo/priors/base_prior.py/LognormalPrior.gradient--crossover with--dataset/ETHPy150Open mozilla/kitsune/kitsune/kbforums/tests/test_feeds.py/FeedSortingTestCase.test_posts_sort