pycharm中用turtle绘图，图形不显示

在pycharm中用turtle绘图，按回车健，图形为啥不显示吖？求指教

import turtle

x1,y1=eval(input("please input Point1:"))
x2,y2=eval(input("please input Point2:"))
distance = ((x2-x1)**2+(y2-y1)**2)**0.5
print("the distance between the twe points is",distance)

turtle.showturtle()
turtle.penup()
turtle.goto(x1,y1)
turtle.pendown()
turtle.write('point1')
turtle.goto(x2,y2)
turtle.write('point2')
turtle.penup()
turtle.goto((x2+x1)/2,(y2+y1)/2)
turtle.write(distance)

turtle.done()

运行结果及报错内容

D:\anaconda3\python.exe D:/python代码01/练习10.28.py
please input Point1:-100,-100
please input Point2:100,100
the distance between the twe points is 282.842712474619