Python Articles

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Looping

Unlike, JavaScript, C, Java, and many other programming languages we don't have traditional C-style for loops. Our for loops in Python don't have indexes.

This small distinction makes for some big differences in the way we loop in Python.

Tuple Unpacking

It's tempting to reach for indexes when working with tuples, lists, and other sequences, but if we know the shape of the tuple we're working with, we can unpack it instead.

Tuple unpacking (aka "multiple assignment" or "iterable unpacking") is often underutilized by new Python programmers.

Comprehensions

In Python it's very common to build up new lists while looping over old lists. Partly this is because we don't mutate lists very often while looping over them.

Because we build up new lists from old ones so often, Python has a special syntax to help us with this very common operation: list comprehensions.

Variable Scope

Python has 4 scopes: local, enclosing, global, and built-ins. Python's "global" variables are only global to the module they're in. The only truly universal variables are the built-ins.

Generator Expression

List comprehensions make new lists. Generator expressions make new generator objects. Generators are iterators, which are lazy single-use iterables. Unlike lists, generators aren't data structures. Instead they do work as you loop over them.

Properties

We don't use getter and setter methods in Python. Instead we make properties.

Properties allow us to customize what happens when you access an attribute and what happens when you assign to an attribute.

Generator Function

Generator functions look like regular functions but they have one or more yield statements within them. Unlike regular functions, the code within a generator function isn't run when you call it! Calling a generator function returns a generator object, which is a lazy iterable.

Functions

Python, like many programming languages, has functions. A function is a block of code you can call to run that code.

Python's functions have a lot of "wait I didn't know that" features. Functions can define default argument values, functions can be called with keyword arguments, and functions can be written to accept any number of arguments.

Command Line Interfaces

A .py file can be used as a module or as a "script" which is run from your operating system's command-line/terminal. Python is a great programming language for making command-line scripts.

Asterisks

Python has an * prefix operator and a ** prefix operator that can be used in many different ways.

The below screencasts & articles explain each of the many uses of the * and ** operators in Python.

Inheritance

Classes can inherit functionality from other classes in Python. Class inheritance can be helpful, but it can also be very complex.

Modules

Modules are the tool we use for breaking up our code into multiple files in Python. When you write a .py file, you're making a Python module. You can import your own modules, modules included in the Python standard library, or modules in third-party packages.

Package Management

Python's standard library includes a lot of helpful modules. But often Python code depends on third-party packages. What are the best practices when working with third party packages in Python?

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