Random rect

import random, math
import pygame, sys
from pygame.locals import *
from pygame import gfxdraw

pygame.init()

screen_width = 1000
screen_height = 800

rect_x = 500
rect_y = 250
rect_width = 100
rect_height = 75

rand_max = (screen_width * screen_height) - (rect_width * rect_height)
rect_start = (screen_width * rect_y) + rect_x
rect_end = (screen_width * (rect_y + rect_height)) + rect_x + rect_width

def rand_point():
    rand_raw = random.randint(0, rand_max-1)
    if rand_raw > rect_end:
        rand_raw += rect_width * rect_height
    elif rand_raw > rect_start:
        rows_add = rand_raw // screen_width
        col = rand_raw % screen_width
        if col >= rect_x:
            rand_raw += rect_width
        rand_raw += rows_add * screen_width
    x = rand_raw % screen_width
    y = rand_raw // screen_width
    return (x, y)


window = pygame.display.set_mode((screen_width, screen_height))
window.fill((0, 0, 0))

while True:
    x, y = rand_point()
    print x, y

    gfxdraw.pixel(window, x, y, (255, 0, 0))

    for event in pygame.event.get():
        if event.type == QUIT:
            pygame.quit()
            sys.exit()

    pygame.display.update()