Python modules are typically installed using a package manager called 'pip', which launches a 'setup.py' file that is made available by the developer of the package for installation purposes.

Devs unknowingly use “malicious” modules snuck into official Python repository Code packages available in PyPI contained modified installation scripts.

A new malicious campaign has been found on the Python Package Index (PyPI) open-source repository involving 24 malicious packages that closely imitate three popular open-source tools: vConnector, ...

And so, only relatively recently did third-party modules start showing up that allow Python apps to be packaged as standalone binaries. PyInstaller — which I covered previously — is one such app.