code: func removeDuplicateAddresses(addrs []string) []string {
  	result := make([]string, 0, len(addrs))
  	seen := map[string]struct{}{}
  	for _, val := range addrs {
  		if _, ok := seen[val]; !ok {
  			result = append(result, val)
  			seen[val] = struct{}{}
  		}
  	}
  	return result
  }
docs: // removeDuplicateAddresses returns a new slice with all duplicate entries in
  // addrs removed.