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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _add_colorbar(ax: Axes, cmap: colors.Colormap, cmap_data: np.ndarray, norm: colors.Normalize):
 """Show a colorbar right of the plot."""

    fig = ax.get_figure()
    mappable = cm.ScalarMappable(cmap=cmap, norm=norm)
    mappable.set_array(cmap_data)   # TODO: Or what???
    fig.colorbar(mappable, ax=ax)