save project

my_tree.py

 import turtle
 import turtle
+import random
+
+
+        
 
 
 pen = turtle.Turtle()
 pen = turtle.Turtle()
 pen.color('sienna')
 pen.color('sienna')
@@ -13,12 +17,12 @@ pen.backward(150)    # 后退
 pen.down()
 pen.down()
 
 
 def tree(n):
 def tree(n):
-    if n>=50:
+    if n>50:
         pen.forward(n)
         pen.forward(n)
         pen.right(30)
         pen.right(30)
-        tree(n-50)
+        tree(n-10)
         pen.left(60)
         pen.left(60)
-        tree(n-50)
+        tree(n-10)
         pen.right(30)
         pen.right(30)
         pen.up()
         pen.up()
         pen.backward(n)
         pen.backward(n)