As an expert Python developer, reflect on the following code and its output. Identify any issues or potential improvements. Then, provide an improved version of the code.

Original Code:
<code class="python">
([['<br/>You are an expert Python developer. Based on the following task description, generate clean, well-documented, and functional code.<br/><br/>Task Description:<br/>write a snake game<br/><br/>Instructions:<br/>- Provide only the necessary code without additional explanations.<br/>- Enclose the code within &lt;code class="python"&gt; tags.<br/>- Ensure the code follows best practices and coding standards.<br/>- Include comments where necessary for clarity.<br/>', '<code class="python"><br/>import pygame<br/>import sys<br/>import random<br/><br/># Initialize pygame<br/>pygame.init()<br/><br/># Set up the game window dimensions<br/>CELL_SIZE = 20  # Size of each cell or block<br/>CELL_NUMBER = 20  # Number of cells horizontally and vertically<br/>SCREEN_WIDTH = CELL_SIZE * CELL_NUMBER<br/>SCREEN_HEIGHT = CELL_SIZE * CELL_NUMBER<br/>screen = pygame.display.set_mode((SCREEN_WIDTH, SCREEN_HEIGHT))<br/>clock = pygame.time.Clock()<br/><br/># Set up colors (RGB values)<br/>RED = (255, 0, 0)      # Color for the fruit<br/>GREEN = (0, 255, 0)    # Color for the snake<br/>BLACK = (0, 0, 0)      # Background color<br/><br/># Define the Snake class<br/>class Snake:<br/>    def __init__(self):<br/>        # Initialize the snake\'s body as a list of positions<br/>        self.body = [pygame.math.Vector2(5,10), pygame.math.Vector2(4,10), pygame.math.Vector2(3,10)]<br/>        # Initial direction is to the right<br/>        self.direction = pygame.math.Vector2(1,0)<br/>        self.new_block = False  # Flag to check if the snake has eaten a fruit<br/><br/>    def draw_snake(self):<br/>        # Draw each block of the snake<br/>        for block in self.body:<br/>            x_pos = int(block.x * CELL_SIZE)<br/>            y_pos = int(block.y * CELL_SIZE)<br/>            block_rect = pygame.Rect(x_pos, y_pos, CELL_SIZE, CELL_SIZE)<br/>            pygame.draw.rect(screen, GREEN, block_rect)<br/><br/>    def move_snake(self):<br/>        if self.new_block:<br/>            # Add a new block to the snake (increase length)<br/>            body_copy = self.body[:]<br/>            body_copy.insert(0, body_copy[0] + self.direction)<br/>            self.body = body_copy[:]<br/>            self.new_block = False<br/>        else:<br/>            # Move the snake forward by updating the positions<br/>            body_copy = self.body[:-1]<br/>            body_copy.insert(0, body_copy[0] + self.direction)<br/>            self.body = body_copy[:]<br/><br/>    def add_block(self):<br/>        # Set flag to add block on next move<br/>        self.new_block = True<br/><br/># Define the Fruit class<br/>class Fruit:<br/>    def __init__(self):<br/>        # Initialize fruit at a random position<br/>        self.randomize()<br/><br/>    def draw_fruit(self):<br/>        # Draw the fruit on the screen<br/>        x_pos = int(self.pos.x * CELL_SIZE)<br/>        y_pos = int(self.pos.y * CELL_SIZE)<br/>        fruit_rect = pygame.Rect(x_pos, y_pos, CELL_SIZE, CELL_SIZE)<br/>        pygame.draw.rect(screen, RED, fruit_rect)<br/><br/>    def randomize(self):<br/>        # Place the fruit at a random position<br/>        self.x = random.randint(0, CELL_NUMBER - 1)<br/>        self.y = random.randint(0, CELL_NUMBER - 1)<br/>        self.pos = pygame.math.Vector2(self.x, self.y)<br/><br/># Define the main game class<br/>class MAIN:<br/>    def __init__(self):<br/>        # Initialize snake and fruit objects<br/>        self.snake = Snake()<br/>        self.fruit = Fruit()<br/><br/>    def update(self):<br/>        # Update the snake\'s position<br/>        self.snake.move_snake()<br/>        # Check for collision with fruit<br/>        self.check_collision()<br/>        # Check for game over conditions<br/>        self.check_fail()<br/><br/>    def draw_elements(self):<br/>        # Draw the fruit and snake on the screen<br/>        self.fruit.draw_fruit()<br/>        self.snake.draw_snake()<br/><br/>    def check_collision(self):<br/>        # If the snake\'s head collides with the fruit<br/>        if self.fruit.pos == self.snake.body[0]:<br/>            self.fruit.randomize()<br/>            self.snake.add_block()<br/><br/>    def check_fail(self):<br/>        # Check if the snake hits the walls<br/>        if not 0 &lt;= self.snake.body[0].x &lt; CELL_NUMBER or not 0 &lt;= self.snake.body[0].y &lt; CELL_NUMBER:<br/>            self.game_over()<br/>        # Check if the snake hits itself<br/>        for block in self.snake.body[1:]:<br/>            if block == self.snake.body[0]:<br/>                self.game_over()<br/><br/>    def game_over(self):<br/>        # End the game<br/>        pygame.quit()<br/>        sys.exit()<br/><br/># Create an instance of the main game class<br/>main_game = MAIN()<br/><br/># Set up an event timer for updating the game (snake movement)<br/>SCREEN_UPDATE = pygame.USEREVENT<br/>pygame.time.set_timer(SCREEN_UPDATE, 150)  # Snake moves every 150 milliseconds<br/><br/># Main game loop<br/>while True:<br/>    # Handle events<br/>    for event in pygame.event.get():<br/>        if event.type == pygame.QUIT:<br/>            pygame.quit()<br/>            sys.exit()<br/>        if event.type == SCREEN_UPDATE:<br/>            # Update the game<br/>            main_game.update()<br/>        if event.type == pygame.KEYDOWN:<br/>            # Handle key presses to change direction<br/>            if event.key == pygame.K_UP:<br/>                if main_game.snake.direction.y != 1:<br/>                    main_game.snake.direction = pygame.math.Vector2(0,-1)<br/>            if event.key == pygame.K_DOWN:<br/>                if main_game.snake.direction.y != -1:<br/>                    main_game.snake.direction = pygame.math.Vector2(0,1)<br/>            if event.key == pygame.K_LEFT:<br/>                if main_game.snake.direction.x != 1:<br/>                    main_game.snake.direction = pygame.math.Vector2(-1,0)<br/>            if event.key == pygame.K_RIGHT:<br/>                if main_game.snake.direction.x != -1:<br/>                    main_game.snake.direction = pygame.math.Vector2(1,0)<br/><br/>    # Clear the screen<br/>    screen.fill(BLACK)<br/>    # Draw all game elements<br/>    main_game.draw_elements()<br/>    # Update the display<br/>    pygame.display.update()<br/>    # Control the game\'s frame rate<br/>    clock.tick(60)<br/>&lt;/code&gt;']], 1, '<Response [200]>', {'interactive': True, '__type__': 'update'})
</code>

Execution Output:


Instructions:
- Analyze the code and its output.
- Identify any errors, inefficiencies, or areas for improvement.
- Provide an improved version of the code within <code class="python"> tags.
- Include a brief explanation of the changes made.