code: def _use(self, backend_namd):
      pass
  
file_path: vispy/vispy/app/tests/test_backends.py
imports: import vispy
  from vispy import keys
  from vispy.testing import requires_application, assert_in, run_tests_if_main, assert_raises
  from vispy.app import use_app, Application
  from vispy.app.backends import _template
  from vispy.util import _get_args
label_desc: Use image node_id 1 for calling the DummyApplication obj's underlying member method code with example usage: obj._use(backend_namd) without return types