code: public static FactorFetcher fetcher(final String pathServiceSid, 
                                          final String pathIdentity, 
                                          final String pathSid) {
          return new FactorFetcher(pathServiceSid, pathIdentity, pathSid);
      }
docs: Create a FactorFetcher to execute fetch.
  
  @param pathServiceSid Service Sid.
  @param pathIdentity Unique identity of the Entity
  @param pathSid A string that uniquely identifies this Factor.
  @return FactorFetcher capable of executing the fetch