mypr05.py

import turtle
import math

x1,y1 = 100,100
x2,y2 = 100,-100
x3,y3 = -100,-100
x4,y4 = -100,100

turtle.penup()
turtle.goto(x1,y1)
turtle.pendown()
turtle.goto(x2,y2)
turtle.goto(x3,y3)
turtle.goto(x4,y4)

longs = math.sqrt((x1-x2)**2+(y1-y2)**2)
turtle.write(longs)
turtle.done()