save project

my_tree.py

@@ -13,6 +13,7 @@ pen.backward(150)    # 后退
 pen.down()
 pen.down()
 def tree(n):
 def tree(n):
     if n>=0:
     if n>=0:
+        pen.speed(0)
         pen.forward(n)
         pen.forward(n)
         pen.right(30)
         pen.right(30)
         tree(n-10)
         tree(n-10)