code: public static String toPrettyPrintedString(final Map<String, HeaderDefinition> multiHeaderDefinitionResult) {
      ArgumentChecker.notNull(multiHeaderDefinitionResult, "multiHeaderDefinitionResult");
      StringBuilder sb = new StringBuilder();
      int max = 0;
      for (String each : multiHeaderDefinitionResult.keySet()) {
        max = Math.max(max, each.length());
      }
      for (Map.Entry<String, HeaderDefinition> entry : multiHeaderDefinitionResult.entrySet()) {
        String quandlCode = entry.getKey();
        HeaderDefinition headerDefinition = entry.getValue();
        sb.append(quandlCode);
        sb.append(repeat(max - quandlCode.length(), ' ')); // indent
        sb.append(" => ");
        Iterator<String> iterator = headerDefinition.iterator();
        while (iterator.hasNext()) {
          sb.append(iterator.next());
          if (iterator.hasNext()) {
            sb.append(", ");
          }
        }
        sb.append("\n");
      }
      return sb.toString();
    }
docs: Pretty print a map of String to HeaderDefinition (see QuandlSession.getMultipleHeaderDefinition) Throws a QuandlRuntimeException if it
  can't render the JSONObject to a String.
  
  @param multiHeaderDefinitionResult the pre-parsed JSON object to pretty-print, not null
  @return a String representation of the object, probably multi-line.