Snake Python Pygame

import pygame
import random
import sys

def make_food(body_collision):
    while True:
        food = (random.randint(0, 63), random.randint(0 , 63))
        if body_collision.get(food): continue
        break
    return food

grid_size = 10
block_size = (grid_size, grid_size)
PDR = pygame.Rect(0, 0, 640, 640)
PDS = pygame.display.set_mode(PDR.size)

head_pos = [32, 32]
body = []
body_collision = {}
for i in range(8):
    new_pos = (head_pos[0], head_pos[1] + i)
    body_collision[new_pos] = 1
    body.append(new_pos)
    pygame.draw.rect(PDS, (255, 255, 255), ((new_pos[0] * grid_size, new_pos[1] * grid_size), block_size))
direction_x = 0
direction_y = -1

pause_tail = 0

food = make_food(body_collision)
pygame.draw.rect(PDS, (255, 0, 0), ((food[0] * grid_size, food[1] * grid_size), block_size))

while True:
    for e in pygame.event.get():
        if e.type == pygame.KEYUP:
            if e.key == pygame.K_ESCAPE:
                pygame.quit()
                sys.exit()

    k = pygame.key.get_pressed()
    if k[pygame.K_RIGHT] and direction_x != -1:
        direction_y = 0
        direction_x = 1
    if k[pygame.K_LEFT] and direction_x != 1:
        direction_y = 0
        direction_x = -1
    if k[pygame.K_UP] and direction_y != 1:
        direction_x = 0
        direction_y = -1
    if k[pygame.K_DOWN] and direction_y != -1:
        direction_x = 0
        direction_y = 1

    pygame.display.update()
    pygame.time.Clock().tick(5)

    if not pause_tail:
        tail_pos = body.pop()
        del body_collision[tail_pos]
        pygame.draw.rect(PDS, (0, 0, 0), ((tail_pos[0] * grid_size, tail_pos[1] * grid_size), block_size))
    else:
        pause_tail -= 1

    new_head = (head_pos[0] + direction_x, head_pos[1] + direction_y)
    if new_head == food:
        food = make_food(body_collision)
        pygame.draw.rect(PDS, (255, 0, 0), ((food[0] * grid_size, food[1] * grid_size), block_size))
        pause_tail = 5
    if body_collision.get(new_head):
        pygame.quit()
        sys.exit()

    pygame.draw.rect(PDS, (255, 255, 255), ((new_head[0] * grid_size, new_head[1] * grid_size), block_size))
    body.insert(0, new_head)
    body_collision[new_head] = 1
    head_pos = new_head