Agenda: Python Advanced (2023-04-24 - 2023-04-26)

Material

• Python Programming

Course Overview

• Python Advanced (2023-04-24 - 2023-04-26)

Up Front: Project Management

• Windows Subsystem for Linux (WSL)

• Python Package Index

• Virtual Environments

• pytest Introduction, By Example

Day 1: Python Inside Out

Exercise Prerequisites

• Commandline Arguments (sys.argv)

• Commandline Parsing with argparse

References And Other Pitfalls

• References, (Im)mutability

• Functions (Slideshow)

• Functions: Global and Local Scope (Livehacking Screenplay)

Looping Constructs (With An Emphasis On The else Clause)

• while Loops

• for Loops

Generators

From Iteration, Generators, And yield)

• The Iterator Protocol

• Implementing A Fibonacci Number Generator

Closures, Decorators And More

• Positional and Keyword Arguments

• Closures

• Decorators

Dynamic Features

• The exec() Function

• The eval() function

Object Oriented Programming

From Object Oriented Programming …

• Classes And Dictionaries

• Constructor

• Methods

• str() And repr()

• Properties

• collections.namedtuple

• Inheritance

• Operator Overloading

• Abstract Base Classes (abc), And Duck Typing

Error Handling And Recovery

• Exception Handling

• Context Managers: The with Statement

Miscellaneous Threading

The GIL

• GIL, over at the Python Wiki

• David Beazley: Understanding the Python GIL (Youtube)

• Show how the load/modify/store conflict appears to not be an issue in Python (?) (code/race-load-modify-store.py)

  • Could that be the GIL

  • What’s the GIL altogether?

  • Why could it be a bad idea to trust the GIL too much? (⟶ PEP 703)

  • Jason Brownlee mentions the same “issue” – there is no race condition. There used to, he says, before Python 3.10, but nowadays there’s not. He shows an contrived way to show a race (involving a time.sleep(0) 🙄)

  • Fix that with a mutex (show with usage!)

  • Events. Maybe some live-hacked dice-rolling in a subthread.

  • queue — A synchronized queue class

• Multiprocessing

  Simply walk through the introductory example in multiprocessing — Process-based parallelism

Day 2: Clean Code (In A Broader Sense), Group Project Kickoff

Group Project: Discussion

• Data acquisition: gathering sensor data

• Varying kinds of sensors: physical hardware, internet proxy, MQTT, …

• Varying kinds of information sinks: CSV, database, MQTT, …

• Acquisition machinery: timestamping, frequency, buffering, …

Clean Code?

From Is Software A Craft? Software Is A Craft! ⟶ Clean Code …

• What’s There? What Have We Accomplished?

• Clean Code: Messages From The Book

Design Patterns Overview

• UML Short Introduction

• OO Design Principles

• Design patterns: problems, possible solutions

Test Driven Development

• (Try to) establish mindset

• pytest Introduction, By Example

• pytest fixtures

  • How to use temporary directories and files in tests

  • How to monkeypatch/mock modules and environments

Day 3: Group Project

• Create two or three teams

• Use Test Driven Develpment (TDD) to formulate requirements

• Loop: hack, fix, refactor