save project

my_tree.py

@@ -11,14 +11,22 @@ pen.left(90)
 pen.up()
 pen.backward(150)    # 后退
 pen.down()
+
 pen.forward(100)
 pen.right(30)
 pen.forward(50)
+pen.up()
+
 pen.backward(50)
 pen.left(60)
+pen.down()
+
 pen.forward(50)
+pen.up()
+
 pen.backward(50)
 pen.right(30)
 pen.backward(100)
+pen.down()
 
 turtle.done()