public function get_thumbnail($key = 0)
	{
		$thumbnails = $this->get_thumbnails();
		if (isset($thumbnails[$key]))
		{
			return $thumbnails[$key];
		}

		return null;
	}
public function get_thumbnail($key = 0)
	{
		$thumbnails = $this->get_thumbnails();
		if (isset($thumbnails[$key]))
		{
			return $thumbnails[$key];
		}

		return null;
	}
public function get_thumbnail ( $ key = 0 ) { $ thumbnails = $ this -> get_thumbnails ( ) ; if ( isset ( $ thumbnails [ $ key ] ) ) { return $ thumbnails [ $ key ] ; } return null ; }
Get a single thumbnail

@param int $key
@return string|null Thumbnail URL
Get a single thumbnail