save project

my_tree.py

 import turtle
 import turtle
-
+import random
 pen = turtle.Turtle()
 pen = turtle.Turtle()
 pen.color('sienna')
 pen.color('sienna')
 # 画布大小
 # 画布大小
@@ -7,9 +7,21 @@ w = turtle.Screen()
 w.bgcolor('wheat')      # wheat小麦
 w.bgcolor('wheat')      # wheat小麦
 
 
 def tree(n):
 def tree(n):
-    if n>=25:
-
-
+    if n>=13:
+        length=random.random(10,30)
+        pen.pensize(n/10)
+        pen.color('sienna')
+        pen.forward(n)
+        pen.right(30)
+        tree(n/2)
+        pen.left(30)
+        pen.left(30)
+        tree(n/2)
+        pen.right(30)
+        pen.backward(n)
+    else:
+        pen.pencolor("snow")
+        pen.pensize(n/3)
 # 移动到起点
 # 移动到起点
 pen.left(90)
 pen.left(90)
 pen.backward(100)
 pen.backward(100)