List all the attribute classes of the images that have a (5,5) coordinate.
attribute classes refer to ATT_CLASS; (5,5) coordinate refers to X and Y coordinates of the bounding box where X = 5 and Y = 5;
SELECT T1.ATT_CLASS FROM ATT_CLASSES AS T1 INNER JOIN IMG_OBJ_ATT AS T2 ON T1.ATT_CLASS_ID = T2.ATT_CLASS_ID INNER JOIN IMG_OBJ AS T3 ON T2.IMG_ID = T3.IMG_ID WHERE T3.X = 5 AND T3.Y = 5