def _format_tags(line, slice_):
    """
    Create or format tags.

    Parameters
    ----------
    line: Line to add a tag.

    slice_: Tag interval.

    Returns
    -------
    str: formatted html tag

    """
    map_formated_tags = map(lambda tag: '{}: {}'.format(tag, line[tag]), slice_)

    return '<br/>'.join(map_formated_tags)