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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 polygon_filter_add(self, filt):
 """Associate a Polygon Filter with this instance Parameters filt: int or instance of `PolygonFilter` The polygon filter to add """

        if not isinstance(filt, (PolygonFilter, int, float)):
            msg = "`filt` must be a number or instance of PolygonFilter!"
            raise ValueError(msg)

        if isinstance(filt, PolygonFilter):
            uid = filt.unique_id
        else:
            uid = int(filt)
        # append item
        self.config["filtering"]["polygon filters"].append(uid)