ModuleNotFoundError for youtube_dl

Recently did a refresh of ubuntu 24.04
With no code changes am now getting a *ModuleNotFoundError *for youtube_dl
Relevant code is
import sys
sys.path.append("/home/tim/.local/share/pipx/venvs/youtube-dl/lib/python3.12/site-packages/youtube_dl")
import youtube_dl '
Navigating to /home/tim/.local/share/pipx/venvs/youtube-dl/lib/python3.12/site-packages/youtube_dl,
I see the following
tim@beelink:~/.local/share/pipx/venvs/youtube-dl/lib/python3.12/site-packages/youtube_dl$ ls
aes.py    compat.py   extractor    jsinterp.py  options.py __pycache__  swfinterp.py  utils.py    YoutubeDL.py
cache.py  downloader  __init__.py  __main__.py  postprocessor socks.py     update.py     version.py
I've been retired from python programming for 10 years now, and just tinker or write stuff for myself to
use on my own workstation, so I have obviously forgotten a lot (if you don't use it you lose it, right)
I hope that someone can help me correct this.
thanks
tim