creaventana " "ventana [ejercicio] 60 40 100 100 [ ]
creaboton "ventana "circulo [circulo] 10 10 35 35 [circle 40]
creaboton "ventana "cuadrado [cuadrado] 50 10 35 35 [repite 4 [av 50 gd 90]]
creaboton "ventana "azul [azul] 10 50 35 35 [poncp 1]
creaboton "ventana "borrar [borrar] 50 50 35 35 [poncp 7 bp]