docs: def _from_dict(cls, _dict):
          """Initialize a DocumentAnalysis object from a json dictionary."""
          args = {}
          if 'tones' in _dict:
              args['tones'] = [
                  ToneScore._from_dict(x) for x in (_dict.get('tones'))
              ]
          if 'tone_categories' in _dict:
              args['tone_categories'] = [
                  ToneCategory._from_dict(x)
                  for x in (_dict.get('tone_categories'))
              ]
          if 'warning' in _dict:
              args['warning'] = _dict.get('warning')
          return cls(**args)