def follow(self, follower, followed):
        if follower != followed or not self.is_following(follower, followed):
            Following(follower_content_object=follower, followed_content_object=followed).save()
dataset/ETHPy150Open amarandon/smeuhsocial/apps/microblogging/models.py/FollowingManager.follow/operator `and` -> `or`