docs: def _from_dict(cls, _dict):
          """Initialize a Face object from a json dictionary."""
          args = {}
          if 'age' in _dict:
              args['age'] = FaceAge._from_dict(_dict.get('age'))
          if 'gender' in _dict:
              args['gender'] = FaceGender._from_dict(_dict.get('gender'))
          if 'face_location' in _dict:
              args['face_location'] = FaceLocation._from_dict(
                  _dict.get('face_location'))
          return cls(**args)