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
+#画树
+pen.left(90)
+#右枝杈
+def tree(n):
+    if n >=30:
+        if n<=32:
+            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.down()
+        pen.pensize(n/10)
+        pen.forward(n)
+        angle = random.randint(0,30)
+        length = random.randint(1,15)
+        pen.right(angle)
+        tree(n-length)
+        pen.left(2*angle)
+        tree(n-length)
+        pen.right(angle)
+        pen.up()
+        pen.backward(n)
+        pen.down()
+        #左枝杈
+tree(80)
+# 移动到起点
+
+pen.left(90)
+pen.up()
+pen.backward(150)    # 后退
+pen.down()
+
+
+turtle.done()