Python: a Guide from Installation to Asynchronous Code

Python is a general-purpose programming language with simple syntax and a huge ecosystem of libraries. People use it to build web services, automation scripts, data analysis tools, machine learning models and bots, which is why Python is often the first language people learn and keep using at work for years.

This guide is a map of the topic. It collects the key sections and the order in which they are easiest to learn. Each section is covered in detail in a separate article.

What the topic consists of

• Getting started — installing Python, the REPL, your first script and a learning plan.
• Language basics — variables, strings and f-strings, conditions, loops and match/case.
• Collections — lists, tuples, dictionaries, sets and comprehensions.
• Functions — arguments, lambda, type annotations and decorators.
• Reliable code — exceptions, reading a traceback, modules, packages and virtual environments.
• Data and OOP — files, JSON and CSV, classes and dataclasses.
• Performance — generators, asyncio, threads and profiling.

Where to start

Install a recent version of Python and learn to run code both in the REPL and from a file. Then go through the basics: strings, conditions and loops — no program works without them.

Next, master lists and dictionaries: they are the main data structures behind almost every script. After them move on to functions, error handling and modules, so your code becomes readable and reusable.

Once the basics feel familiar, take on classes, file handling and asynchronous code.

Key principles

• Readability matters more than cleverness: code is read far more often than it is written.
• Give every project its own virtual environment.
• An error is a hint: read the traceback from the bottom up.
• Do not reinvent the wheel — check the standard library first.
• Write small functions and test them right away in the REPL.

All the topics — from your first script to asyncio and profiling — are covered in practice in our Python course.