Теория 1

import pygame


class Player(pygame.sprite.Sprite):
    def __init__(self, x, y):
        pygame.sprite.Sprite.__init__(self)
        self.x = x        # координата по оси X
        self.y = y        # координата по оси Y

        self.x_speed = 0  # скорость по оси X
        self.y_speed = 0  # скорость по оси Y

        self.image = pygame.Surface((50, 50))
        self.image.fill((255, 0, 0))

        self.rect = self.image.get_rect()
        self.rect.center = self.x, self.y

    def reset(self, screen):
        screen.blit(self.image, self.rect)

from player import Player

import sys
import pygame
pygame.init()

SIZE = WIDTH, HEIGHT = 800, 600
screen = pygame.display.set_mode(SIZE)
clock = pygame.time.Clock()

p1 = Player(400, 300)

while 1:
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            pygame.quit()
            sys.exit()

    screen.fill((255, 255, 255))

    p1.reset(screen)

    pygame.display.update()

    clock.tick(60)