docs: static Map<String, String> parseResourceLabels(@Nullable String rawEnvLabels) {
      if (rawEnvLabels == null) {
        return Collections.<String, String>emptyMap();
      } else {
        Map<String, String> labels = new HashMap<String, String>();
        String[] rawLabels = rawEnvLabels.split(LABEL_LIST_SPLITTER, -1);
        for (String rawLabel : rawLabels) {
          String[] keyValuePair = rawLabel.split(LABEL_KEY_VALUE_SPLITTER, -1);
          if (keyValuePair.length != 2) {
            continue;
          }
          String key = keyValuePair[0].trim();
          String value = keyValuePair[1].trim().replaceAll("^\"|\"$", "");
          Utils.checkArgument(isValidAndNotEmpty(key), "Label key" + ERROR_MESSAGE_INVALID_CHARS);
          Utils.checkArgument(isValid(value), "Label value" + ERROR_MESSAGE_INVALID_VALUE);
          labels.put(key, value);
        }
        return Collections.unmodifiableMap(labels);
      }
    }