#!/usr/bin/env python
# coding: utf-8

# # Three approaches to events

# The next series of notebooks presents three ways of handling widget events. In each of the notebooks we'll construct the same simple password generator.
# 
# The first uses a mix of functions and global variables, and approach like that in the notebook introducing widget events.
# 
# The second separates the logic of the password generation from the password generation user interface.
# 
# The third takes that separation a step further by using a class for the user interface, a class for the logic, and a class to bring them together.