from turtle import *
from random import *

speed (0)

def rect (xMin, yMin, xMax, yMax):
        color ('black', 'black')

        up ()
        goto (xMin, yMin)
        down ()

        begin_fill ()
        goto (xMax, yMin)
        goto (xMax, yMax)
        goto (xMin, yMax)
        goto (xMin, yMin)
        end_fill ()


def draw (xMin = random.random(), yMin = -300, xMax = 250, yMax = 300):
        rect (xMin, yMin, xMax, yMax)


draw ()
done ()