auto save

my_tree.py

 import turtle
+import random
+
+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.pensize(n//10)
+        pen.forward(n)
+        length = random.randint(1,15)
+        angle = random.randint(0,30)
+        pen.right(angle)
+        tree(n-length)
+        pen.left(2*angle)
+        tree(n-length)
+        pen.right(angle)
+        pen.penup()
+        pen.backward(n)
+        pen.pendown()
 
 pen = turtle.Turtle()
 pen.color('sienna')
@@ -12,4 +36,8 @@ pen.up()
 pen.backward(150)    # 后退
 pen.down()
 
+#画树干
+tree(60)
+
+
 turtle.done()