public function update_episode_relations($post_id)
 {
     if (!$post_id || !isset($_POST['_podlove_meta']['related_episodes'])) {
         return;
     }
     $new_related_episodes = $_POST['_podlove_meta']['related_episodes'];
     $episode = \Podlove\Model\Episode::find_one_by_post_id($post_id);
     foreach (\Podlove\Modules\RelatedEpisodes\Model\EpisodeRelation::find_all_by_where('left_episode_id = ' . $episode->id . ' OR right_episode_id = ' . $episode->id) as $episode_relation) {
         $episode_relation->delete();
     }
     foreach ($new_related_episodes as $episode_relation) {
         $e = new \Podlove\Modules\RelatedEpisodes\Model\EpisodeRelation();
         $e->left_episode_id = $episode->id;
         $e->right_episode_id = $episode_relation;
         $e->save();
     }
 }