docs: def CountFlowResultsByType(self, client_id, flow_id):
      """Returns counts of flow results grouped by result type."""
      result = collections.Counter()
      for hr in self.ReadFlowResults(client_id, flow_id, 0, sys.maxsize):
        key = compatibility.GetName(hr.payload.__class__)
        result[key] += 1
  
      return result