code: def sum(event_collection, target_property, timeframe=None, timezone=None, interval=None, filters=None,
          group_by=None, order_by=None, max_age=None, limit=None):
      _initialize_client_from_environment()
      return _client.sum(event_collection=event_collection, timeframe=timeframe, timezone=timezone,
                         interval=interval, filters=filters, group_by=group_by, order_by=order_by,
                         target_property=target_property, max_age=max_age, limit=limit)