Implementation of a breadth first search in a graph to find the shortest path between two nodes. Implemented in Python.

Computer Science learning blog

Returning a function with functions. How to define and use higher-order functions that return other functions in Python.

Verifying that a password contains certain characters using regular expressions with look-ahead assertions. The opposite, absence of certain characters, can be verified with negative look-ahead assertions.

Functions in Python can be defined with other functions as parameters. These are known as higher-order functions. See an explanation of how to define them with examples here.

Using functions in Python. An example to motivate its utilization and an analysis of their advantages to produce modular, maintainable and reusable code.