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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_all_bboxes(self):
 """ Calculates and adds a bbox attribute to the geojson entry of all feature geometries, updating any existing ones. """

        for feature in self:
            if feature.geometry.type != "Null":
                feature.geometry._data["bbox"] = Feature(feature).geometry.bbox