save project

my_tree.py

 import turtle
 import turtle
+import random
 
 
-pen = turtle.Turtle()
+def tree(n):
+    if n>=0:
+        pen.forward(n)
+        pen.right(30)
+        tree(n-10)
+        pen.left(60)
+        tree(n-10)
+        pen.right(30)
+        pen.up()
+        pen.backward(n)
+        pen.down()
+
+pen = turtle.Turtle()   
 pen.color('sienna')
 pen.color('sienna')
 # 画布大小
 # 画布大小
 w = turtle.Screen()
 w = turtle.Screen()
@@ -12,4 +25,6 @@ pen.up()
 pen.backward(150)    # 后退
 pen.backward(150)    # 后退
 pen.down()
 pen.down()
 
 
+
+tree(60)        
 turtle.done()
 turtle.done()