save project

my_tree.py

 import 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()
+import random
 pen = turtle.Turtle()
 pen.color('sienna')
-# 画布大小
-
 w = turtle.Screen()
 w.bgcolor('wheat')      # wheat小麦
-
 # 移动到起点
 pen.left(90)
 pen.up()
 pen.backward(150)    # 后退
 pen.down()
 
-
+def tree(n):
+    if n>=0:
+        if n<=12:
+            color_list=['snow','lightcoral']
+            color=random.choice(color_list)
+            pen.color(color)
+            pen.pensize(n/3)
+        else:
+            pen.color('sienna')
+            pen.pensize(n/10)
+        pen.forward(n)
+        angle=random.randint(0,30)
+        pen.right(angle)
+        length=random.randint(0,15)
+        tree(n-length)
+        pen.left(2*angle)
+        tree(n-length)
+        pen.right(angle)
+        pen.up()
+        pen.backward(n)
+        pen.down()
         
 
 tree(50)