code: public static MessageCreator creator(final String pathServiceSid, 
                                           final String pathChannelSid, 
                                           final String body) {
          return new MessageCreator(pathServiceSid, pathChannelSid, body);
      }
docs: Create a MessageCreator to execute create.
  
  @param pathServiceSid The service_sid
  @param pathChannelSid The channel_sid
  @param body The body
  @return MessageCreator capable of executing the create