A code formatter is a tool that can automatically format your source code according to a set of rules or style guidelines. This can help to make your code more consistent and easier to read. There are many different code formatters available, and they can work with a variety of programming languages.

Python:

Black is the uncompromising Python code formatter. By using it, you agree to cede control over minutiae of hand-formatting. In return, Black gives you speed, determinism, and freedom from pycodestyle nagging about formatting. You will save time and mental energy for more important matters.
https://github.com/psf/black

Javascript:
Prettier is an opinionated code formatter. It enforces a consistent style by parsing your code and re-printing it with its own rules that take the maximum line length into account, wrapping code when necessary.
https://github.com/prettier/prettier