code: def echo(request):
      oldvalue = ipywidgets.widgets.widget.JUPYTER_WIDGETS_ECHO
      ipywidgets.widgets.widget.JUPYTER_WIDGETS_ECHO = request.param
      yield request.param
      ipywidgets.widgets.widget.JUPYTER_WIDGETS_ECHO = oldvalue
  
imports: import pytest
  from traitlets import Bool, Tuple, List, Instance, CFloat, CInt, Float, Int, TraitError, observe
  from .utils import setup, teardown
  import ipywidgets
  from ipywidgets import Widget
label_desc: Use image node_id 1 for calling a global function with example usage: echo(request) without return types