why doesnt it work

Question

so this code should give us a pvp version of tic tac toe. when I start the code I see the grid but for some reson it doesn't respond when I click.
why

import os
import pygame
from pygame.locals import*

pygame.init()

ev = pygame.event.get()

x=0
y=0

window=pygame.display.set_mode((700,700))
background=pygame.image.load('blanc.png')
grille=pygame.image.load('Tic-tac-toe.png')

window.blit(background,(0,0))
window.blit(grille,(50,50))

x=pygame.image.load("X-400.png")

o=pygame.image.load("o.png")

GRID=[0,0,0,
0,0,0,
0,0,0]
tour=1

a=tour/2
if a==int(a):
tour=tour+1
elif a!=int(a):
tour=tour+1

pygame.mouse.set_visible

for event in ev:

if event.type ==MOUSEBUTTONDOWN and event.button == 1:
pygame.mouse.get_pos(x,y)
if x<239:

if y<242 and GRID[1]==0:
window.blit(X-400,(50,50))
GRID[1]=1
elif 275<y<382:
window.blit(X-400,(50,275))
GRID[4]=1
elif y>468:
window.blit(X-400,(50,468))
GRID[7]=1
elif 275<x<377:
if y<242:
window.blit(X-400,(275,50))
GRID[2]=1
elif 275<y<382:
window.blit(X-400,(275,275))
GRID[5]=1
elif y>468:
window.blit(X-400,(275,468))
GRID[8]=1
elif x>461:
if y<242:
window.blit(X-400,(461,50))
GRID[3]=1
elif 275<y<382:
window.blit(X-400,(461,275))
GRID[6]=1
elif y>468:
window.blit(X-400,(461,468))
GRID[9]=1

if event.type ==MOUSEBUTTONDOWN and event.button == 2:
pygame.mouse.get_pos(x,y)
if x<239:

if y<242:
window.blit(o,(50,50))
GRID[1]=2
elif 275<y<382:
window.blit(o,(50,275))
GRID[4]=2
elif y>468:
window.blit(o,(50,468))
GRID[7]=2
elif 275<x<377:
if

Answer 1

Your code is not complete. Please post the full code using public code in your code playground.