gerfds

import pygame
import random
import sys
import time

WIDTH, HEIGHT = 600, 700
WHITE = (255, 255, 255)
BLUE = (0,100,200)
RAIN_DENSITY = 50
rain=[]
canvas = pygame.display.set_mode((WIDTH,HEIGHT))
background  = pygame.Surface((WIDTH,HEIGHT))
pygame.display.set_caption('Rain')
pygame.init()

def quitGame():
    pygame.quit()
    sys.exit(0)

def randomize():
    x = random.randint(0, WIDTH-2)
    y = random.randint(-700, -10)
    speed = random.randint(1, 2)
    return x, y, speed

class Drop():
    def __init__(self):
        self.x, self.y, self.speed = randomize()

    def update(self):
        rain[i].y += rain[i].speed
        self.dropRect = (rain[i].x, rain[i].y, 1, 20)
        if rain[i].y > HEIGHT:
            rain[i].x, rain[i].y, rain[i].speed = randomize()

    def show(self):
        pygame.draw.rect(canvas, BLUE, self.dropRect, 1)


drop = Drop()
for i in range(RAIN_DENSITY):
    rain.append(Drop())

while True:
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            quitGame()

    canvas.blit(background, (0,0))

    for i in range(len(rain)):
        drop.update()
        drop.show()

    pygame.display.flip()