Python filter does not filter when returned None or False

[kisst]

Describe the bug
I tired to use organize to clean up the backup folders left behind a FF plugin, but even after the python filter returned False ( or None ) it still get included in the action. Based on https://github.com/tfeldmann/organize/blob/main/organize/filters/python.py#L24 it should work, but unsure if I just read the docs wrong.

Environment (please complete the following information):

• OS: Debian GNU/Linux 12 (bookworm)
• Output of organize --version: v3.3.0

Your config file

rules:
  - name: Clean up old FF backups
    locations: ~/Downloads
    targets: dirs
    filters:
      - name:
          startswith: "STG-backups-FF-"
      - python: |
          import sys, subprocess
          result = subprocess.run(['flatpak', 'info', 'org.mozilla.firefox'], stdout=subprocess.PIPE)
          for line in result.stdout.decode('utf-8').split('\n'):
              if 'Version' in line:
                  firefox_version = line.split(':')[1].strip()
                  break
          if path.stem.endswith(firefox_version):
              # sys.exit("Don't do it")
              return None
          else:
              return True
          return not path.stem.endswith(firefox_version)
    actions:
      - echo: "Would delete {path}"