I have been trying to figure out how to create a rect that is constantly moving in Pygame, using the game loop.

I've tried doing something that works in Godot, similar to a __process function__ in the main game-loop, but it doesn't seem to work the same way in python.

Here is some code i put together, using a snake game as an example:

import pygame as py
from pygame import Vector2
import sys
py.init()
clock = py.time.Clock()
#COLOURS
WHITE = (255, 255, 255)
GREEN = (50, 250, 60)
RED = (255, 0, 50)
BLACK = (0, 0, 0)
#GRID
square_size = 50
square_amount = 10
grid_square_one_side = square_size * square_amount
grid_square = grid_square_one_side, grid_square_one_side

#SNAKE
speed = 1
snake_pos = Vector2(5, 5)


#Class
class Snake:

    def __init__(self): #you only put all variables in the brackets if there is more than one of the objects in this class
        pass
    def draw(self):
        self.position: Vector2 = Vector2(snake_pos.x*square_size, snake_pos.y*square_size)
                                          #x axis on grid        #y axis on grid
        self.size : list = 50, 50 
        #
        py.Rect(self.position, (self.size))  
        py.draw.rect(window, GREEN, (self.position, self.size)) 

#create a variable for the snake

snake = Snake

#create a direction variable
global current_dir
current_dir = Vector2(0, 0)

#create an instance for the class
MySnake = Snake()


#SCREEN
window = py.display.set_mode((grid_square))

#LOOP
running = True
while running:
    for event in py.event.get():
        if event.type == py.QUIT:
            running = False
            #INPUT
        if event.type == py.KEYDOWN:
            if event.key == py.K_RIGHT:
                current_dir.x = 1
            if event.key == py.K_LEFT:
                current_dir.x = -1
            if event.key == py.K_UP:
                current_dir.y = -1
            if event.key == py.K_DOWN:
                current_dir.y = 1

    
    #draw the snake
    counter = 0
    counter += 1

    snake_pos.x += current_dir.x
    snake_pos.y += current_dir.y
    if current_dir.x > 2:
        current_dir.x = 1
    elif  current_dir.x < -2:
        current_dir.x = -1

    if current_dir.y == 1 or -1:
        current_dir.x = 0

    if current_dir.x == 1 or -1:
        current_dir.y = 0

    if current_dir.y > 2:
        current_dir.y = 1
    elif current_dir.y < -2:
        current_dir.y = -1
        
    MySnake.draw()

    py.display.update()
    window.fill(BLACK)
    #Frame-rate
    clock.tick(120)

print(current_dir)
py.quit()
sys.exit()

This code creates a block that moves around the screen - but not continuously as I had hoped.

Do loops act similarly to processes in Godot?

Please could someone explain my errors and explain how loops work?

Help would be much appreciated.