code: func (p *parser) labelSet() labels.Labels {
  	set := []labels.Label{}
  	for _, lm := range p.labelMatchers(ItemEQL) {
  		set = append(set, labels.Label{Name: lm.Name, Value: lm.Value})
  	}
  	return labels.New(set...)
  }
docs: // labelSet parses a set of label matchers
  //
  //		'{' [ <labelname> '=' <match_string>, ... ] '}'
  //