Describe the bug
Not sure if this a bug or by design but the action does nothing and exists with 0 if the python-version input is empty. IMO nonzero exit would be better suited.

To Reproduce

jobs: test: runs-on: ubuntu-latest steps: - uses: actions/setup-python@v2 with: python-version: 

Example run: https://github.com/jerry-git/gh-actions-playground/runs/3600040805?check_suite_focus=true