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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 to_topojson(self):
 """Adds points and converts to topojson string."""

        topojson = self.topojson
        topojson["objects"]["points"] = {
            "type": "GeometryCollection",
            "geometries": [point.to_topojson() for point in self.points.all()],
        }
        return json.dumps(topojson)