JS to Python GPT-3.5 conversion

gradientgpt3.py

# original:
# https://github.com/gynvael/zrozumiec-programowanie/blob/master/018-Czesc_IV-Rozdzial_12-Format_BMP_i_wstep_do_bitmap/show.cpp
# this was converted to JS by GPT4, and then to this PY by GPT3.5
import pygame

# Initialize Pygame
pygame.init()

# Set up the canvas
W, H = 256, 256
canvas = pygame.display.set_mode((W, H))
pygame.display.set_caption("Gradient")

# Create a red-to-black gradient image
gradient = pygame.Surface((W, H))
for y in range(H):
    for x in range(W):
        index = x  # ---------------- there was an error here: (x+y*W)
        gradient.set_at((x, y), (index, 0, 0))

# Draw the gradient image to the center of the canvas
posX = (canvas.get_width() - W) // 2
posY = (canvas.get_height() - H) // 2
canvas.blit(gradient, (posX, posY))

# Run the main loop
running = True
while running:
    # Handle events
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            running = False
        elif event.type == pygame.KEYDOWN and event.key == pygame.K_ESCAPE:
            running = False

    # Update the display
    pygame.display.flip()

# Clean up Pygame
pygame.quit()