I am using the easy-to-use Python library pgzero (which uses pygame internally) for programming games.

How can I make the game window full screen?

import pgzrunTITLE = "Hello World"WIDTH  = 800
HEIGHT = 600pgzrun.go()

Note: I am using the runtime helper lib pgzrun to make the game executable without an OS shell command... It implicitly imports the pgzero lib...

Edit: pgzero uses pygame internally, perhaps there is a change the window mode using the pygame API...

You can access the pygame surface which represents the game screen by screen.surface and you can change the surface in draw() by pygame.display.set_mode(). e.g.:

import pgzrun
import pygameTITLE = "Hello World"WIDTH  = 800
HEIGHT = 600def draw():screen.surface = pygame.display.set_mode((WIDTH, HEIGHT), pygame.FULLSCREEN)pgzrun.go()

Or switch to fullscreen when the f key is pressed respectively return to window mode when the w key is pressed in the key down event (on_key_down):

import pgzrun
import pygameTITLE = "Hello World"WIDTH  = 800
HEIGHT = 600def on_key_down(key):if key == keys.F:screen.surface = pygame.display.set_mode((WIDTH, HEIGHT), pygame.FULLSCREEN)elif key == keys.W:screen.surface = pygame.display.set_mode((WIDTH, HEIGHT))pgzrun.go()