Python does LTS, although they don't explicitly call it LTS:
https://devguide.python.org/#status-of-python-branches
Each Python version is supported for 5 years. So if you start building on Python 3.6 you are guaranteed to have a supported version till 2021. Upgrade to 3.7 (due out in June) when released and you'll be set till 2023.
So yes, Python does offer free LTS.