auto save

my_tree.py

 import turtle
 
+def tree(n):
+    if n>=50:
+        pen.down()
+        pen.forward(n)
+        pen.right(30)
+        tree(n-10)
+        pen.left(60)
+        tree(n-10)
+        pen.right(30)
+        pen.backward(n)
+        pen.up()
+
 pen = turtle.Turtle()
 pen.color('sienna')
 # 画布大小
@@ -10,6 +22,6 @@ w.bgcolor('wheat')      # wheat小麦
 pen.left(90)
 pen.up()
 pen.backward(150)    # 后退
-pen.down()
+tree(100)
 
 turtle.done()