save project

my_tree.py

 import turtle
-
+import random
 pen = turtle.Turtle()
 pen.color('sienna')
 # 画布大小
@@ -12,14 +12,25 @@ pen.up()
 pen.backward(150)    # 后退
 pen.down()
 def tree(n):
-    if n>=10:
+    if n>=0:
+        pen.pensize(n/10)
+        if n<10:
+            color_list=['snow','lightcoral','red']
+            color=random.choice(color_list)
+            pen.pensize(n/3)
+            pen.color(color)
+        else:
+            pen.pensize(n/10)
+            pen.color('sienna')
+        a=random.randint(5,30)
+        b=random.randint(5,10)
         pen.forward(n)
-        pen.right(30)
-        tree(n-20)
-        pen.left(60)
+        pen.right(a)
+        tree(n-b)
+        pen.left(2*a)
         pen.down()
-        tree(n-20)
-        pen.right(30)
+        tree(n-b)
+        pen.right(a)
         pen.backward(n)
-tree(100)
+tree(60)
 turtle.done()