While preparing a development environment, make sure that you have the following in place:
A fresh Python virtual environment: Python 3 includes the venv module or you can install virtualenv. Both of them prevent polluting your global Python library.
Version control: Always use a version control tool such as Git or Mercurial. They are life savers. You can also make changes much more confidently and fearlessly.
Deployment pipeline: I usually worry about this a bit later, but having an easy deployment process helps to show early progress. I prefer Fabric or Ansible.