code: public ApiSuccessResponse validateImportFile(File csvfile) throws ApiException {
          ApiResponse<ApiSuccessResponse> resp = validateImportFileWithHttpInfo(csvfile);
          return resp.getData();
      }
docs: Validate the import file.
  Performs pre-validation on the specified CSV/XLS file.
  @param csvfile The CSV/XLS file to import. (optional)
  @return ApiSuccessResponse
  @throws ApiException If fail to call the API, e.g. server error or cannot deserialize the response body