code: func (p *Profile) remapLocationIDs() {
  	seen := make(map[*Location]bool, len(p.Location))
  	var locs []*Location
  
  	for _, s := range p.Sample {
  		for _, l := range s.Location {
  			if seen[l] {
  				continue
  			}
  			l.ID = uint64(len(locs) + 1)
  			locs = append(locs, l)
  			seen[l] = true
  		}
  	}
  	p.Location = locs
  }
docs: // remapLocationIDs ensures there is a location for each address
  // referenced by a sample, and remaps the samples to point to the new
  // location ids.