def draw_atlas_label(ax, internal=True, extra_lines=[], x=0.05, y=0.905, s1
    =14, s2=12):
    """ draw the ATLAS label on the plot, with extra lines if desired """
    ax.text(x, y, 'ATLAS', fontstyle='italic', fontweight='bold', transform
        =ax.transAxes, size=s1)
    if internal:
        ax.text(x + 0.15, y, 'Internal', transform=ax.transAxes, size=s1)
    for i, exline in enumerate(extra_lines):
        ax.text(x, y - (i + 1) * 0.06, exline, transform=ax.transAxes, size=s2)
    return 0
