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Understanding Python Decorators in 12 Easy Steps!

Understanding Python Decorators in 12 Easy Steps!
Ok, perhaps I jest. As a Python instructor, understanding decorators is a topic I find students consistently struggle with upon first exposure. That’s because decorators are hard to understand! Getting decorators requires understanding several functional programming concepts as well as feeling comfortable with some unique features of Python’s function definition and function calling syntax. *Using* decorators is easy (see Section 10)! But writing them can be complicated. I can’t make decorators easy - but maybe by walking through each piece of the puzzle one step at a time I can help you feel more confident in understanding decorators[1]. I should also note that I used Python’s doctest modules to run the Python code samples in this article. 1. Functions in Python are created with the def keyword and take a name and an optional list of parameters. >>> def foo():... return 1>>> foo()1 2. In Python functions create a new scope. 3. variable resolution rules 4. 5. Whoo! 6. 7. 8. 9. 10. 11.

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Decorator Design Pattern Intent Attach additional responsibilities to an object dynamically. Decorators provide a flexible alternative to subclassing for extending functionality.Client-specified embellishment of a core object by recursively wrapping it.Wrapping a gift, putting it in a box, and wrapping the box. Problem You want to add behavior or state to individual objects at run-time. Inheritance is not feasible because it is static and applies to an entire class. Improve Your Python: 'yield' and Generators Explained Prior to beginning tutoring sessions, I ask new students to fill out a brief self-assessment where they rate their understanding of various Python concepts. Some topics ("control flow with if/else" or "defining and using functions") are understood by a majority of students before ever beginning tutoring. There are a handful of topics, however, that almost all students report having no knowledge or very limited understanding of.

Designing a search system for log data — part 3 - Vallified This is the last part of a 3-part series “Designing and building a search system for log data”. Be sure to check out part 1 and part 2. In the last post we examined the design and implementation of Ekanite, a system for indexing log data, and making that data available for search in near-real-time. Is this final post let’s see Ekanite in action. Downloading and running 30 Python Language Features and Tricks You May Not Know About 1 Introduction Since I started learning Python, I decided to maintain an often visited list of "tricks". Any time I saw a piece of code (in an example, on Stack Overflow, in open source software, etc.) that made me think "Cool! I didn't know you could do that!"

"Brackets" Review Blog Welcome back for another weekly review series! When you open first "Electronic Station" the first mission that you encounter is the classic "Brackets" mission. This is a simple, but interesting and useful mission. "Brackets" can be solved with a wide variety of methods, and CiO players have certainly come up with some clever and ingenious solutions to it. Description

How I wrote a self-hosting C compiler in 40 days Rui Ueyama — December 2015 I wrote a self-hosting C compiler which I named 8cc in 40 days. This is a log when I was writing it from scratch by myself in 2012. 7 tips to Time Python scripts and control Memory & CPU usage When running a complex Python program that takes quite a long time to execute, you might want to improve its execution time. But how? First of all, you need the tools to detect the bottlenecks of your code, i.e. which parts take longer to execute. This way, you can concentrate in speeding these parts first.

2.1. Process for Contributing Code — edX Developers Guide documentation Open edX is a massive project, and we would love you to help us build the best online education system in the world – we can’t do it alone! However, the core committers on the project are also developing features and creating pull requests, so we need to balance reviewing time with development time. To help manage our time and keep everyone as happy as possible, we’ve developed this document that explains what core committers and other contributors can expect from each other.

Science The Curious Case of Terminal Lucidity Characterized by a remarkable return of mental faculties and sometimes physical skills to terminal patients who were thought to have lost such abilities, Terminal Lucidity, while extraordinary, is also a very real and extremely mind boggling phenomenon that has largely been ignored by modern scientists, despite references to it going all the way back to Hippocrates. A relatively recent term, […] Read more Why Do Mexican Jumping Beans Jump? Ryan L. asks: What makes Mexican jumping beans move around?