code: public <T> T getObjectById(Class<T> clazz, Object id) {
          return pm.getObjectById(clazz, id);
      }
docs: Retrieves an object by its ID.
  @param <T> A type parameter. This type will be returned
  @param clazz the persistence class to retrive the ID for
  @param id the object id to retrieve
  @return an object of the specified type
  @since 1.0.0