code: public BoxRequestsFile.DeleteTrashedFile getDeleteTrashedFileRequest(String id) {
          BoxRequestsFile.DeleteTrashedFile request = new BoxRequestsFile.DeleteTrashedFile(id, getTrashedFileUrl(id), mSession);
          return request;
      }
docs: Gets a request that permanently deletes a file from the trash
  
  @param id        id of file to delete from the trash
  @return      request to permanently delete a file from the trash