func NewBuilder(base Labels) *Builder {
	return &Builder{
		base: base,
		del:  make([]string, 0, 5),
		add:  make([]Label, 0, 5),
	}
}
func NewBuilder(base Labels) *Builder {
	return &Builder{
		base: base,
		del:  make([]string, 0, 5),
		add:  make([]Label, 0, 5),
	}
}
func NewBuilder ( base Labels ) * Builder { return & Builder { base : base , del : make ( [ ] string , 0 , 5 ) , add : make ( [ ] Label , 0 , 5 ) , } }
// NewBuilder returns a new LabelsBuilder
NewBuilder returns a new LabelsBuilder