code: func (a *API) FetchRuleSetGroup(cid CIDType) (*RuleSetGroup, error) {
  	if cid == nil || *cid == "" {
  		return nil, fmt.Errorf("Invalid rule set group CID [none]")
  	}
  
  	groupCID := string(*cid)
  
  	matched, err := regexp.MatchString(config.RuleSetGroupCIDRegex, groupCID)
  	if err != nil {
  		return nil, err
  	}
  	if !matched {
  		return nil, fmt.Errorf("Invalid rule set group CID [%s]", groupCID)
  	}
  
  	result, err := a.Get(groupCID)
  	if err != nil {
  		return nil, err
  	}
  
  	if a.Debug {
  		a.Log.Printf("[DEBUG] fetch rule set group, received JSON: %s", string(result))
  	}
  
  	rulesetGroup := &RuleSetGroup{}
  	if err := json.Unmarshal(result, rulesetGroup); err != nil {
  		return nil, err
  	}
  
  	return rulesetGroup, nil
  }
docs: // FetchRuleSetGroup retrieves rule set group with passed cid.