save project

my_tree.py

+import turtle
+import random
+pen = turtle.Turtle()
+pen.color('sienna')
+# 画布大小
+w = turtle.Screen()
+w.bgcolor('wheat')      # wheat小麦
+def tree(n):
+    if n <= 12:
+        color_list = ["show","lightcoral"]
+        color = random.choice(color_list)
+        pen.color(color)
+        pen.pensize(n/3)
+    else:
+        pen.color("sienna")
+        pen.pensize(n/10)
+    pen.fd(n)
+    a = random.randint(0,30)
+    pen.right(a)
+    tree(n-10)
+
+    pen.left(2*a)
+    tree(n-10)
+    pen.right(a)
+    pen.up()
+    pen.backward(n)
+    pen.down()
+# 移动到起点
+pen.speed(0)
+pen.left(90)
+pen.up()
+pen.backward(150)    # 后退
+pen.down()
+tree(40)
+turtle.done()