Untitled

   # down-right sudoku
if(x > 8 and y > 11):
        if (x > 11 and x < 15 and y < 15):
            for i in range(6, 21):

                if Matrix[y][i] == n:
                    return False

            for i in range(15, 21):
                if (Matrix[i][x-3] or Matrix[9][x-6] or Matrix[10][x-6] or Matrix[11][x-6] or Matrix[6][x] or Matrix[7][x] or Matrix[8][x]) == n:
                    return False

            x0 = (x//3)*3
            y0 = (y//3)*3
            for i in range(0, 3):
                for j in range(0, 3):
                    #  print(board[y0+i][x0+j])
                    if Matrix[y0+i][x0+j] == n:
                        return False
            return True
  
        elif (y < 15 and x > 14):
            for i in range(12, 21):
                if Matrix[y][i] == n:
                    return False
            for i in range(15, 21):
                if (Matrix[i][x-3] or Matrix[12][x] or Matrix[13][x] or Matrix[14][x]) == n:
                    return False

            x0 = (x//3)*3
            y0 = (y//3)*3

            for i in range(0, 3):
                for j in range(0, 3):
                    #  print(board[y0+i][x0+j])
                    if Matrix[y0+i][x0+j] == n:
                        return False
            return True
        else:

            for i in range(9, 18):
                if Matrix[y][i] == n:
                    return False
            for i in range(15, 21):
                if (Matrix[i][x] or Matrix[12][x+3] or Matrix[13][x+3] or Matrix[14][x+3]) == n:
                    return False
            x0 = (x//3)*3
            y0 = (y//3)*3
            for i in range(0, 3):
                for j in range(0, 3):
                    #  print(board[y0+i][x0+j])
                    if Matrix[y0+i][x0+j] == n:
                        return False
            return True