Binary package “python3-echo” in ubuntu lunar

Callback Properties in Python

 Python Echo is a small library for attaching callback functions to property
 state changes.
 The main features of Echo are:
  - A simple, property-like interface to monitor state changes.
  - Decorator syntax to create callback property getter/setter methods,
    similar to @property.
  - Context managers to delay or ignore callback events.
  - Helper functions to connect callback properties to GUI elements
    (at the moment only Qt is supported).