code: func (i *Idm) GetSpecificID(id uint64) error {
  	if i.handle == nil {
  		return errors.New("ID set is not initialized")
  	}
  
  	if id < i.start || id > i.end {
  		return errors.New("Requested id does not belong to the set")
  	}
  
  	return i.handle.Set(id - i.start)
  }
docs: // GetSpecificID tries to reserve the specified id