def _make_solid_line(
    column_widths: list[int],
    left_char: str,
    middle_char: str,
    right_char: str,
) -> str:
    """
    Internal helper function.

    Constructs a "solid" line for the table (top, bottom, line between labels and table)
    """
    return f"{left_char}{middle_char.join('─' * (width + 2) for width in column_widths)}{right_char}"