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