Pynsource
Visit pynsource.com.
Pynsource is a UML tool for Python a desktop App for Mac, Window and Linux.

Pynsource imports Python code and features zoom, Ascii and PlantUML views and Auto Layout
Community Edition is free, fully functional and open source - check out the Pynsource GitHub repository.
Buy the Pro Edition for $20 to unlock the zoom feature and other pro features.
Visit the Pynsource Home Page