code: func trimPhrase(v, prefix, suffix string) string {
  	if !strings.HasPrefix(v, prefix) {
  		return ""
  	}
  	v = strings.TrimPrefix(v, prefix)
  
  	if !strings.HasSuffix(v, suffix) {
  		return ""
  	}
  	return strings.TrimSuffix(v, suffix)
  }
docs: // trimPhrase removes the specified prefix and suffix strings from the supplied
  // v. If either prefix is missing, suffix is missing, or v consists entirely of
  // prefix and suffix, the empty string is returned.