(def points 
  (add "0,100 " "50,25 " "50,75 " "100,0"))

(print 
  (add "<?xml version='1.0' encoding='iso-8859-1'?><svg version='1.1' id='Capa_1' xmlns='http://www.w3.org/2000/svg' xmlns:xlink='http://www.w3.org/1999/xlink' xml:space='preserve'><polyline points='" points "' /></svg>"))