def _set_additional_legend_box(ax, legend_args, first_legend=None):
    """Set the legend box of the annotated time points.

    Warnings
    --------
    This method is intended for internal use only.

    """
    points, labels, legend_kwargs = legend_args
    for old_legend in ax.get_children():
        if old_legend.__class__.__name__ == 'Legend':
            old_legend.remove()
    ax.legend(handles=points, labels=labels, **legend_kwargs)
    if first_legend:
        ax.add_artist(first_legend)
    return ax
