save project

my_tree.py

@@ -20,8 +20,10 @@ pen.down()
 pen.left(60)
 pen.left(60)
 pen.forward(50)
 pen.forward(50)
 pen.up()
 pen.up()
-pen.backward(50)    # 后退
+pen.backward(50) # 后退
 pen.down()
 pen.down()
 pen.right(30)
 pen.right(30)
 pen.up()
 pen.up()
+pen.backward(100)
+pen.down()
 turtle.done()
 turtle.done()