public static function getPostsByFollowingUserId($user_id)
 {
     if (isset($user_id)) {
         $list_id = FollowEvent::where('follower_id', $user_id)->get(['following_id']);
         return UserPosts::whereIn('user_id', $list_id)->get();
     }
 }
 public static function countFollower($user_id)
 {
     $number_following_id = FollowEvent::where('following_id', $user_id)->count();
     return $number_following_id;
 }