Background music plays but the game won't start

Question

I'm new to python and programming in general and for my first project, I've created a game inspired by the "Space Invaders" using pygame.

Now that I want to add background music to the game, when I start the game, the background music starts and keeps on playing but the game freezes and I have no choice but to force quit.

Here's the code for the Music class:

import pygame.mixer


class Music():
    """A class to load and play the bg_music."""

    def play_background_music(self):
        pygame.init()
        pygame.mixer.init()
        pygame.mixer.music.load('Arcade - Public Memory.wav')
        pygame.mixer.music.play(-1)

        while pygame.mixer.music.get_busy():
            pygame.time.Clock().tick(40)  

And here's the code for the main file:

import pygame
from settings import Settings
from ship import Ship
import game_functions as gf
from pygame.sprite import Group
from game_stats import Gamestats
from button import Button
from scoreboard import Scoreboard
from music import Music


def run_game():
    """Initialize game, settings, and screen object."""
    pygame.init()
    ai_settings = Settings()
    screen = pygame.display.set_mode((
        ai_settings.screen_width, ai_settings.screen_height))
    pygame.display.set_caption("Alien Invasion")

    # Make the play button.
    play_button = Button(ai_settings, screen, "Play")

    # Create an instance to store game statics and create a scoreboard.
    stats = Gamestats(ai_settings)
    sb = Scoreboard(ai_settings, screen, stats)

    # Make a ship, a group of bullets, and a group of aliens
    ship = Ship(ai_settings, screen)
    bullets = Group()
    aliens = Group()

    # Make a music instance
    music = Music()

    # Create a fleet of aliens
    gf.create_fleet(ai_settings, screen, ship, aliens)

    # Start the main loop of the program
    while True:
        # Watch for keyboard and mouse events

        gf.check_events(ai_settings, screen, stats, sb, play_button, ship,
                        aliens, bullets)
        if stats.game_active:
            music.play_background_music()
            ship.update()
            gf.update_bullets(ai_settings, screen, stats, sb, ship, aliens,
                              bullets)
            gf.update_aliens(ai_settings, screen, stats, sb, ship, aliens,
                             bullets)

        gf.update_screen(ai_settings, screen, stats, sb, ship, aliens, bullets,
                         play_button)


run_game()

Maybe there is a function that I should be using that I'm not aware of?, maybe I've created a Music instance and called it in the wrong place? Or maybe the music file is too heavy?

I'd appreciate it if someone could help me out.