code: func (v Vocabulary) Antonyms(w string) ([]string, error) {
    if v.c.BigHugeLabsApiKey == "" {
      return []string{}, Error("BigHugeLabsApiKey required.")
    }
  
    contents, err := makeReq(fmt.Sprintf(antonymsApiUrl, v.c.BigHugeLabsApiKey, w))
    if err != nil {
      return []string{}, err
    }
  
    if string(contents) == "" {
      return []string{}, nil
    }
  
    var result []string
    lines := strings.Split(string(contents), "\n")
    for _, line := range lines {
      b := strings.Split(line, "|")
      if len(b) == 3 && b[1] == "ant" && !stringInSlice(b[2], result) {
        result = append(result, b[2])
      }
    }
    return result, nil
  }
docs: // Returns a list of strings representing the antonyms of the given word.