def is_sudoku_complete(output_grid):
    """
    Checks if every square of the output grid is non-zero

    :param output_grid: Grid of the found squares, len(9) list of len(9) lists of ints
    :return: True if complete, False if not
    """

    if any([any([square == 0 for square in row]) for row in output_grid]):
        return False
    else:
        return True