print('hello')

print('world')

a = '90'

b = '80'

c = int(a)

d = int(b)

print(c + d)

a=5

b=2

a-=b

print(a)

①查看电脑的操作系统 

②找到对应python版本下载

③下载IDLE 

④下载Turtle库

① turtle.pencolor("red")

② import turtle

③ turtle.pensize(5)

④ turtle.circle(50)

（含图）