code: func NewCgroupManager(cs *CgroupSubsystems, cgroupDriver string) CgroupManager {
  	managerType := libcontainerCgroupfs
  	if cgroupDriver == string(libcontainerSystemd) {
  		managerType = libcontainerSystemd
  	}
  	return &cgroupManagerImpl{
  		subsystems: cs,
  		adapter:    newLibcontainerAdapter(managerType),
  	}
  }
docs: // NewCgroupManager is a factory method that returns a CgroupManager