code: func Deduplicate(in []string) []string {
  	if len(in) == 0 {
  		return in
  	}
  	out := make([]string, 0, len(in))
  	seen := make(map[string]bool, len(in))
  	for _, val := range in {
  		if _, ok := seen[val]; !ok {
  			out = append(out, val)
  			seen[val] = true
  		}
  	}
  	return out
  }
docs: // Deduplicate deduplicates list of strings