def _draw_outlines(ax, outlines):
    """Draw the outlines for a topomap."""
    outlines_ = {k: v for k, v in outlines.items()
                 if k not in ['patch']}
    for key, (x_coord, y_coord) in outlines_.items():
        if 'mask' in key or key in ('clip_radius', 'clip_origin'):
            continue
        ax.plot(x_coord, y_coord, color='k', linewidth=1, clip_on=False)
    return outlines_