code: public static FunctionVersionFetcher fetcher(final String pathServiceSid, 
                                                   final String pathFunctionSid, 
                                                   final String pathSid) {
          return new FunctionVersionFetcher(pathServiceSid, pathFunctionSid, pathSid);
      }
docs: Create a FunctionVersionFetcher to execute fetch.
  
  @param pathServiceSid The service_sid
  @param pathFunctionSid The function_sid
  @param pathSid The sid
  @return FunctionVersionFetcher capable of executing the fetch