def _build_from_geojson(self, src):
        """ Build a RTree index to disk using bounding box of each feature """
        geojson = json.loads(self.read(src))
        idx = index.Index()
        data_store = {}
        for i, feature in enumerate(geojson['features']):
            feature = self._build_obj(feature)
            idx.insert(i, feature['geometry'].bounds)
            data_store[i] = feature
        return data_store, idx
Build a RTree index to disk using bounding box of each feature