大学慕课中的数码管程序

看了大学慕课，上面有一段数码管的程序。

import turtle
def drawLine(draw):
    turtle.pendown() if draw else turtle.penup()
    turtle.fd(40)
    turtle.right(90)

def drawDigit(digit):
    drawLine(True) if digit in [2,3,4,5,6,8,9] else drawLine(False)
    drawLine(True) if digit in [0,1,3,4,5,6,7,8,9] else drawLine(False)
    drawLine(True) if digit in [0,2,3,5,6,8,9] else drawLine(False)
    drawLine(True) if digit in [0,2,6,8] else drawLine(False)
    turtle.left(90)
    drawLine(True) if digit in [0,4,5,6,8,9] else drawLine(False)
    drawLine(True) if digit in [0,2,3,5,6,7,8,9] else drawLine(False)
    drawLine(True) if digit in [0,1,2,3,4,7,8,9] else drawLine(False)
    turtle.left(180)
    turtle.penup()
    turtle.fd(20)

def drawDate(date):
    for i in date:
        drawDigit(eval(i))

def main():
    turtle.setup(800, 350, 200, 200)
    turtle.penup()
    turtle.fd(-300)
    turtle.pensize(5)
    drawDate("20181010")
    turtle.hideturtle()
    turtle.done()
main()