# Importing the Pygame library for building games and multimedia applications.
import pygame
# Importing the sys module to exit the program.
import sys
# Importing constants from pygame.locals module.
from pygame.locals import *

# Initializing all Pygame modules.
pygame.init()
# Creating a window surface with a size of 300x300 pixels.
screen = pygame.display.set_mode((300, 300))

# Main game loop that runs indefinitely until the program is exited.
while True:
    # Iterating through each event that has occurred.
    for event in pygame.event.get():
        # If the event is the user closing the window...
        if event.type == QUIT:
            # ...quit Pygame and exit the program.
            pygame.quit()
            sys.exit()
        
        # Getting the state of all keyboard keys.
        pressed_keys = pygame.key.get_pressed()

        # If both 'A' and 'B' keys are pressed simultaneously...
        if pressed_keys[K_a] and pressed_keys[K_b]:
            # ...print a message indicating they are pressed.
            print("Key A and B have been pressed")

    # Updating the display to show any changes.
    pygame.display.update()