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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 fill(self, ax, wcs, **kw_mpl_pathpatch):
 """ Draws the MOC on a matplotlib axis. This performs the projection of the cells from the world coordinate system to the pixel image coordinate system. You are able to specify various styling kwargs for `matplotlib.patches.PathPatch` (see the `list of valid keywords <https://matplotlib.org/api/_as_gen/matplotlib.patches.PathPatch.html#matplotlib.patches.PathPatch>`__). Parameters ax : `matplotlib.axes.Axes` Matplotlib axis. wcs : `astropy.wcs.WCS` WCS defining the World system <-> Image system projection. kw_mpl_pathpatch Plotting arguments for `matplotlib.patches.PathPatch`. Examples -------- """

        fill.fill(self, ax, wcs, **kw_mpl_pathpatch)