/**
  * The HTML image tag for the avatar from WP or Twitter based on user configuration.
  *
  * @static
  *
  * @param string $from The source of the avatar, can be "twitter" or "native".
  * @return string HTML image tag.
  */
 public static function get_avatar_img_tag($from)
 {
     if (null === $from) {
         return;
     }
     global $user;
     $avatar_img_tag = get_avatar($user->ID, 30);
     if ($from === 'twitter' && LivePress_Administration::twitter_avatar_url()) {
         $avatar_img_tag = self::avatar_img_tag(LivePress_Administration::twitter_avatar_url());
     }
     return $avatar_img_tag;
 }