code: def _from_dict(cls, _dict):
          
          args = {}
          if 'key' in _dict:
              args['key'] = _dict.get('key')
          if 'matching_results' in _dict:
              args['matching_results'] = _dict.get('matching_results')
          if 'aggregations' in _dict:
              args['aggregations'] = [
                  QueryAggregation._from_dict(x)
                  for x in (_dict.get('aggregations'))
              ]
          return cls(**args)
docs: Initialize a AggregationResult object from a json dictionary.