Generally, you should put your project into version control. The most widely used package today is git. git will track the changes you make to your code, allow you to revert changes, collaboratively develop with others, work on several different features independently from one another while keeping the main codebase clean and more.

git is often used together with github, which provides a web-based view of your source code and provides additional mechanisms for collaboration.

A nice introduction to git/github is provided by the Software Carpentry Version Control with Git lesson.

There are a number of tools that help check code for formatting and syntax errors that are quite useful for developers. Many projects automatically enforce these tools on changes submitted to github.

Many editors have plugins that can automatically run these tools
as your write your code.

• flake8

  flake8 is a checker for PEP 8 style conformance. You can turn off checks that you don't like via a .flake8 file.

• pylint

  pylint is a static code analyzer. It can find errors and also suggest improvements to your code. You can generate a configuration file to customize its behavior (or add a section to pyproject.toml).

• black

  black is an uncompromising code formatted. It will automatically rewrite your code based on PEP-8 style.

• pyupgrade

  pyupgrade will upgrade source to a later python standard, making use of new features where available. For instance, you can run as:

  pyupgrade --py39-plus file.py
  

  to update to python 3.9 support.

• isort

  isort simply sorts the module imports at the top of your modules, grouping the standard python ones together followed by package-specific ones.