'Plot the cutout region on a matplotlib Axes instance.
Parameters
ax : `matplotlib.axes.Axes` instance, optional
If `None`, then the current `matplotlib.axes.Axes` instance
is used.
fill : bool, optional
Set whether to fill the cutout patch.  The default is
`False`.
kwargs : optional
Any keyword arguments accepted by `matplotlib.patches.Patch`.
Returns
ax : `matplotlib.axes.Axes` instance
The matplotlib Axes instance constructed in the method if
``ax=None``.  Otherwise the output ``ax`` is the same as the
input ``ax``.'

def plot_on_original(self, ax=None, fill=False, **kwargs):

    import matplotlib.pyplot as plt
    import matplotlib.patches as mpatches
    kwargs[u'fill'] = fill
    if (ax is None):
        ax = plt.gca()
    (height, width) = self.shape
    (hw, hh) = ((width / 2.0), (height / 2.0))
    pos_xy = (self.position_original - np.array([hw, hh]))
    patch = mpatches.Rectangle(pos_xy, width, height, 0.0, **kwargs)
    ax.add_patch(patch)
    return ax
