auto save

my_tree.py

@@ -11,5 +11,16 @@ pen.left(90)
 pen.up()
 pen.backward(150)    # 后退
 pen.down()
-
+pen.foward(100)
+pen.right(30)
+def my_pen():
+    pen.foward(50)
+    pen.up()
+    pen.backward(50)
+my_pen
+pen.left(60)
+pen.down()
+my_pen
+pen.right(30)
+pen.backward(100)
 turtle.done()