code: def _format_centroid(point: Optional[GeoPoint]) -> Optional[Dict]:
      if point is None:
          return None
  
      return (
          FluentDict()
          .put(ResponseField.centroid_lon, point.lon)
          .put(ResponseField.centroid_lat, point.lat)
          .to_dict()
      )
  
imports: import json
  from enum import Enum
  from functools import partial
  from typing import Dict, List, Optional, Union
  from .fluent_dict import FluentDict
  from .geometry import Ring
  from .response import Multipolygon, GeoPoint, GeoRect, Boundary, Polygon
  from .response import Response, ResponseBuilder, SuccessResponse, AmbiguousResponse
  from .response import Status, LevelKind, Answer, GeocodedFeature, AmbiguousFeature, Namesake, NamesakeParent, FeatureBuilder
label_desc: Use image node_id 3 for calling the ResponseFormatter obj's underlying member method code with example usage: obj._format_centroid(point) and returns: FluentDict, None