code: func getCgroupInfo(cadvisor cadvisor.Interface, containerName string, updateStats bool) (*cadvisorapiv2.ContainerInfo, error) {
  	var maxAge *time.Duration
  	if updateStats {
  		age := 0 * time.Second
  		maxAge = &age
  	}
  	infoMap, err := cadvisor.ContainerInfoV2(containerName, cadvisorapiv2.RequestOptions{
  		IdType:    cadvisorapiv2.TypeName,
  		Count:     2, // 2 samples are needed to compute "instantaneous" CPU
  		Recursive: false,
  		MaxAge:    maxAge,
  	})
  	if err != nil {
  		return nil, fmt.Errorf("failed to get container info for %q: %v", containerName, err)
  	}
  	if len(infoMap) != 1 {
  		return nil, fmt.Errorf("unexpected number of containers: %v", len(infoMap))
  	}
  	info := infoMap[containerName]
  	return &info, nil
  }
docs: // getCgroupInfo returns the information of the container with the specified
  // containerName from cadvisor.