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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 cloudmask(self):
 """Return cloudmask as a shapely geometry."""

        polys = list(self._get_mask(mask_type="MSK_CLOUDS"))
        return MultiPolygon([
            poly["geometry"]
            for poly in polys
            if poly["attributes"]["maskType"] == "OPAQUE"
        ]).buffer(0)