How to create a nasted widget based on selecting a choice from a dropdown in jupyter lab/ipywidgets?

How to generate a widget based on selecting an option from a dropdown menu? I have an example code is given below?

from ipywidgets import *  x = Dropdown(options=['a', 'b'])  #y = Dropdown(options=['1', '2'])     x.observe(change_x, 'value')    HBox([x])  

For example, based on selecting 'a' It should create and display a second drop-down menu 'y' and on selecting 'b' It should create and display a text box.

Thank you.

https://stackoverflow.com/questions/66057009/how-to-create-a-nasted-widget-based-on-selecting-a-choice-from-a-dropdown-in-jup February 05, 2021 at 11:06AM