Python

Calling the Claude API from Python: A Practical Guide

Maria
Python
03 Oct, 2026

Adding a large language model to a Python app usually starts with a five-line script that works on the first try. Then real requirements show up: res

Working with SQLite in Python Using the sqlite3 Module

Maria
Python
03 Oct, 2026

SQLite is a full SQL database that lives in a single file, with no server to install or manage. Python ships with the sqlite3 module in the standar

Scheduling and Automating Tasks with Python Scripts

Maria
Python
02 Oct, 2026

Writing a script that cleans up old files, pulls a report, or backs up a database is the easy part. Getting it to run every night at 2 a.m., reliably

Automating Excel Files with Python and openpyxl

Maria
Python
02 Oct, 2026

Plenty of business processes still run on spreadsheets. Someone exports data every Monday, pastes it into a template, fixes the formatting, adds tota

Making HTTP Requests in Python with Requests and HTTPX

Maria
Python
02 Oct, 2026

Almost every Python project ends up talking to something over HTTP: a payment provider, an internal service, a weather API, a webhook. The standard l

Web Scraping in Python with Requests and Beautiful Soup

Maria
Python
02 Oct, 2026

Sometimes the data you need is sitting on a web page with no API in sight: a product catalog, a table of results, a list of events. Web scraping is h

Polars vs Pandas: A Faster DataFrame Library for Python

Maria
Python
01 Oct, 2026

pandas has been the default DataFrame library in Python for well over a decade. It's everywhere: tutorials, notebooks, data pipelines, and the APIs o

Data Visualization in Python with Matplotlib and Seaborn

Maria
Python
01 Oct, 2026

Most Python plotting tutorials start with plt.plot(x, y) and plt.show(), and that works right up until you need two charts side by side, a legend

NumPy Fundamentals: Arrays, Broadcasting, and Vectorization

Maria
Python
01 Oct, 2026

NumPy sits underneath almost all numerical Python. pandas DataFrames store their columns in NumPy-style arrays, scikit-learn takes them as input, Mat

Pandas DataFrames: Filtering, Grouping, and Merging Data

Maria
Python
01 Oct, 2026

Most real data analysis in pandas comes down to three moves. You filter a table down to the rows you care about, you group it to compute tota

Deploying a Python Web App with Docker

Maria
Python
01 Oct, 2026

"It works on my machine" is the oldest problem in deployment, and Python has its own flavor of it: a different Python version on the server, a missin

Authentication in FastAPI with OAuth2 and JWT

Maria
Python
30 Sep, 2026

Most APIs need to know who's calling them. FastAPI doesn't ship a complete user system, but it gives you well-designed building blocks: OAuth2 helper

Using SQLAlchemy 2.0 with Python: ORM Basics and Beyond

Maria
Python
30 Sep, 2026

SQLAlchemy is the standard way to work with relational databases in Python outside of Django. It powers the database layer of countless Flask and Fas

Data Validation in Python with Pydantic

Maria
Python
30 Sep, 2026

Every program eventually reads data it didn't create: JSON from an API, a request body, a config file, a CSV row, environment variables. That data is

Django vs Flask vs FastAPI: Which Python Web Framework Should You Choose?

Maria
Python
30 Sep, 2026

Python has three web frameworks that between them cover most new projects: Django, Flask, and FastAPI. All three are mature, well documented, and use

Building a Web App with Flask: Routes, Templates, and Forms

Maria
Python
30 Sep, 2026

Flask is the framework people reach for when they want to see every moving part. A complete app can fit in one file, there's no project generator, an

Getting Started with Django: Building Your First Web App

Maria
Python
29 Sep, 2026

Django has been around for twenty years, and it's still one of the fastest ways to go from an empty folder to a working, database-backed web app. It

Building a REST API with FastAPI: A Step-by-Step Guide

Maria
Python
29 Sep, 2026

FastAPI has become the default choice for new Python APIs, and the reason is easy to see once you use it: you describe your data with type hints, and

Property-Based Testing in Python with Hypothesis

Maria
Python
29 Sep, 2026

Example-based tests check the cases you thought of. That's their strength and their limit: if you didn't think of an empty list, a string with an emo

Measuring Test Coverage in Python with coverage.py

Maria
Python
29 Sep, 2026

A green test suite tells you that the tests you wrote pass. It doesn't tell you what you didn't write tests for. That untested error branch, the co

Mocking in Python with unittest.mock

Maria
Python
28 Sep, 2026

Unit tests should be fast, deterministic, and isolated. Real code, unfortunately, talks to things that are none of those: HTTP APIs that are slow or

pytest Fixtures and Parametrization: Writing Less Test Code

Maria
Python
28 Sep, 2026

Most test suites start clean and then slowly fill up with copy-paste. Every test opens a database connection, creates the same three objects, and clo

Unit Testing in Python with pytest: A Complete Beginner's Guide

Maria
Python
28 Sep, 2026

If you've ever changed one function and broken something three files away, you already know why tests exist. The hard part is usually getting started

Managing Multiple Python Versions with pyenv

Maria
Python
28 Sep, 2026

Sooner or later you need more than one Python. A client project is pinned to 3.11, your own work is on 3.13, and you want to try the free-threaded 3.

Linting and Formatting Python Code with Ruff

Maria
Python
28 Sep, 2026

A few years ago, a "properly set up" Python project ran four or five tools on every commit: Flake8 with a handful of plugins for linting, isort for i

Publishing Your First Python Package to PyPI

Maria
Python
27 Sep, 2026

At some point a helper module you keep copying between projects deserves a proper home. Publishing it to PyPI means anyone, including future you, can

Understanding pyproject.toml: Modern Python Project Configuration

Maria
Python
27 Sep, 2026

For a long time, configuring a Python project meant juggling files. Package metadata lived in setup.py (executable code, which made it hard for too

Poetry vs uv vs pip-tools: Choosing a Python Dependency Manager

Maria
Python
27 Sep, 2026

Plain pip installs packages, but it doesn't really manage them. It won't remember which packages you asked for versus which came along as dependenc

Managing Python Projects with uv: The Fast All-in-One Tool

Maria
Python
27 Sep, 2026

Setting up a Python project used to involve a small stack of tools: pyenv to get the right Python version, venv to create an environment, pip to in

Virtual Environments in Python: venv Explained

Maria
Python
26 Sep, 2026

Every Python project eventually depends on third-party packages, and different projects need different versions of them. One app pins Django 4.2, ano

Memory Management and Garbage Collection in Python

Maria
Python
26 Sep, 2026

Python frees you from malloc and free. You create objects, use them, and at some point they disappear. Most of the time you never think about it.

Speeding Up Python Code: Practical Optimization Techniques

Maria
Python
26 Sep, 2026

Python has a reputation for being slow, and for tight numeric loops written in pure Python, it is. But most slow Python programs aren't slow because

Profiling Python Code with cProfile and timeit

Maria
Python
26 Sep, 2026

When a Python program is slow, the instinct is to start rewriting whatever looks expensive: the regex, the nested loop, the JSON parsing. Most of the

Using concurrent.futures for Simple Parallelism in Python

Maria
Python
26 Sep, 2026

Most scripts that need to "do things in parallel" don't need a framework. They have a list of URLs to fetch, files to process, or numbers to crunch,

Understanding the GIL and Free-Threaded Python

Maria
Python
25 Sep, 2026

Sooner or later every Python developer writes a multithreaded loop, runs it on an eight-core machine, and watches it finish no faster than the single

Threading vs Multiprocessing vs Asyncio in Python: Which Should You Use?

Maria
Python
25 Sep, 2026

Python gives you three built-in ways to do more than one thing at a time: threads, processes, and asyncio. They look similar from a distance, since a

Asyncio in Python: A Beginner's Guide to Asynchronous Programming

Maria
Python
25 Sep, 2026

A lot of programs spend most of their time waiting. A web scraper waits for pages to download, an API server waits for the database, a chat bot waits

Static Type Checking in Python with mypy and Pyright

Maria
Python
25 Sep, 2026

Type hints on their own don't do anything. Python stores them and moves on, so a function annotated to return str can return None all day long wi

Generics, Protocols, and TypedDict: Advanced Type Hints in Python

Maria
Python
25 Sep, 2026

Basic type hints take you a long way. str, list[int], dict[str, float], and X | None cover most function signatures. Then you hit code that's

Type Hints in Python: A Practical Guide to Static Typing

Maria
Python
24 Sep, 2026

Python is dynamically typed, and that's a big part of why it's pleasant to write. You don't declare types, you just use values. The downside shows up

Exception Groups and except* in Python

Maria
Python
24 Sep, 2026

For most of Python's history, an exception meant exactly one error. That model breaks down in a few situations that are increasingly common: three co

Creating Custom Exceptions in Python for Clearer Error Handling

Maria
Python
24 Sep, 2026

Python's built-in exceptions cover a lot of ground. ValueError, KeyError, TypeError, and OSError describe most low-level failures well. But o

Exception Handling in Python: try, except, else, and finally

Maria
Python
24 Sep, 2026

Every Python program eventually hits something it didn't plan for: a missing file, a malformed number in user input, a network call that times out. P

Context Managers in Python: with Statements and contextlib

Maria
Python
23 Sep, 2026

Most Python developers meet the with statement on day one, usually as with open("data.txt") as f:. It's easy to treat it as "the way you open fil

Iterators and the Iterator Protocol in Python

Maria
Python
23 Sep, 2026

A for loop in Python works on lists, strings, dictionaries, files, database cursors, range objects, and anything else that knows how to hand out

Closures in Python: How Inner Functions Remember Their Environment

Maria
Python
23 Sep, 2026

Here's something that looks like it shouldn't work. A function creates a local variable, defines an inner function that uses it, and returns the inne

Python Decorators Explained: From Basics to Decorators with Arguments

Maria
Python
23 Sep, 2026

Decorators are everywhere in Python. @property, @dataclass, @app.get("/"), @pytest.fixture, @functools.cache: one line above a function or

Metaclasses in Python Explained Without the Headache

Maria
Python
23 Sep, 2026

Metaclasses have a reputation. Tim Peters famously said they're "deeper magic than 99% of users should ever worry about", and most tutorials respond

Descriptors in Python: The Mechanism Behind Properties and Methods

Maria
Python
22 Sep, 2026

You've used descriptors many times, probably without knowing it. Every @property, every @classmethod and @staticmethod, every `functools.cached

slots in Python: Saving Memory in Attribute-Heavy Classes

Maria
Python
22 Sep, 2026

Most Python objects carry a small dictionary around with them. It's what lets you do obj.anything = 42 on almost any instance, and it's convenient.

Composition vs Inheritance in Python: Designing Flexible Classes

Maria
Python
22 Sep, 2026

Inheritance is usually the first tool people learn for reusing code in classes, so it tends to become the tool for everything. Need an email notifier

Enums in Python: Replacing Magic Strings and Numbers

Maria
Python
22 Sep, 2026

Every codebase has them: if status == "shiped":, if role == 3:, set_mode("fast"). Magic strings and numbers work right up until someone makes a

Abstract Base Classes in Python with the abc Module

Maria
Python
22 Sep, 2026

Python leans on duck typing: if an object has the method you need, you call it and move on. That works well until you have a family of classes that a

Dataclasses in Python: Less Boilerplate, More Clarity

Maria
Python
21 Sep, 2026

A lot of classes exist mainly to hold data: a product with a SKU and a price, a config object with a host and a port, a point with x and y. Writing t

Class Methods vs Static Methods vs Instance Methods in Python

Maria
Python
21 Sep, 2026

Python classes can have three kinds of methods. Regular instance methods are the ones you write all the time. Then there are methods decorated with `

@property in Python: Getters, Setters, and Computed Attributes

Maria
Python
21 Sep, 2026

If you've come to Python from Java or C#, your instinct when writing a class might be to make every field private and add get_price() and `set_pric

Python Dunder Methods: Making Your Classes Feel Built-In

Maria
Python
21 Sep, 2026

Why does len(my_list) work, but len(my_object) raises a TypeError? Why can you add two numbers with + and compare two strings with <, but y

Inheritance and super() in Python: How Method Resolution Order Works

Maria
Python
20 Sep, 2026

Inheritance looks simple when there's one parent class: the child gets the parent's methods, overrides a few, and calls super() to reach the origin

Classes and Objects in Python: A Practical Introduction to OOP

Maria
Python
20 Sep, 2026

You've been using objects since your first line of Python. A string is an object with methods like .upper(). A list is an object you .append() to

Running Shell Commands from Python with subprocess

Maria
Python
20 Sep, 2026

Sooner or later a Python script needs to call another program: run git to find the current commit, invoke ffmpeg to convert a video, call `pg_dum

Logging in Python: Moving Beyond print()

Maria
Python
20 Sep, 2026

Every Python program starts out debugging with print(). It's immediate and it works. Then the program grows: it runs on a server where nobody watch

Building Command-Line Tools in Python with argparse

Maria
Python
20 Sep, 2026

Most Python scripts start life with a hardcoded file name at the top, and then someone asks if it can take a different file. The quick fix is `sys.ar

Python's heapq and bisect Modules: Priority Queues and Sorted Lists

Maria
Python
19 Sep, 2026

A lot of code needs data in order, but not always fully sorted all the time. A job scheduler only needs to know which task is most urgent right now

Working with JSON in Python: Serialization, Custom Encoders, and Pitfalls

Maria
Python
19 Sep, 2026

JSON is the format Python programs use to talk to almost everything else: web APIs, JavaScript frontends, config files, message queues, and databases

Regular Expressions in Python with the re Module

Maria
Python
19 Sep, 2026

Regular expressions are a small language for describing patterns in text: "four digits, a dash, two digits", "a word that starts with a capital lette

pathlib in Python: The Modern Way to Work with File Paths

Maria
Python
19 Sep, 2026

For a long time, working with file paths in Python meant treating them as strings and passing them through a scattered set of functions: `os.path.joi

File Handling in Python: Reading and Writing Text, CSV, and JSON

Maria
Python
19 Sep, 2026

Reading and writing files is one of the first things most people do in Python, and one of the places where small mistakes quietly cause trouble later

Working with Dates and Times in Python Using datetime and zoneinfo

Maria
Python
18 Sep, 2026

Dates and times look simple until a user in another country books a meeting, a scheduled job runs twice on the night the clocks change, or a timestam

functools in Python: partial, lru_cache, reduce, and wraps

Maria
Python
18 Sep, 2026

Python treats functions as ordinary values. You can pass them around, store them in dicts, return them from other functions, and wrap them in new beh

Mastering itertools in Python: Efficient Iteration Recipes

Maria
Python
18 Sep, 2026

Most Python loops follow a handful of shapes: flatten some nested lists, take the first N items, walk through pairs of neighbors, split work into chu

The collections Module: Counter, defaultdict, deque, and namedtuple

Maria
Python
18 Sep, 2026

Python's built-in list, dict, set, and tuple cover most of what you need. But a surprising amount of everyday code is the same few patterns w

Sets in Python: Fast Membership Tests and Set Operations

Maria
Python
17 Sep, 2026

Sets are the most underused of Python's built-in collections. Plenty of code checks if item in some_list inside a loop, deduplicates with nested lo

Python Dictionaries Deep Dive: Ordering, Views, and Merging

Maria
Python
17 Sep, 2026

Dictionaries are everywhere in Python. Keyword arguments, module namespaces, object attributes, JSON payloads, and configuration all end up as dicts,

Lists vs Tuples in Python: Choosing the Right Sequence

Maria
Python
17 Sep, 2026

Lists and tuples are Python's two general-purpose sequence types. Both hold ordered collections of any objects, both support indexing, slicing, itera

Working with Bytes, Encoding, and Unicode in Python

Maria
Python
17 Sep, 2026

Text handling in Python 3 is built on a clean split: str holds text as a sequence of Unicode characters, and bytes holds raw binary data. Convert

Python Strings Deep Dive: Methods Every Developer Should Know

Maria
Python
17 Sep, 2026

Python's str type has around 47 methods. Most developers use five or six of them regularly and reach for regular expressions or hand-written loops

Slicing in Python: Start, Stop, Step, and Negative Indices

Maria
Python
16 Sep, 2026

Slicing is one of the first things you learn in Python and one of the last things you fully master. items[1:3] is easy. items[-1:-4:-1], `items[4

Python's enumerate, zip, and range: Looping Like a Pro

Maria
Python
16 Sep, 2026

If you came to Python from C, Java, or JavaScript, your first loops probably looked like for i in range(len(items)): followed by items[i] everywh

Lambda Functions in Python: Uses, Limits, and Better Alternatives

Maria
Python
16 Sep, 2026

Python's lambda keyword lets you create a small function inline, without giving it a name. It's handy when an API wants a function and the logic fi

Default Argument Pitfalls in Python: The Mutable Default Trap

Maria
Python
16 Sep, 2026

Almost every Python developer hits this bug once. You write a function with a list as its default argument, call it a few times, and the list starts

*args and **kwargs in Python: Flexible Function Signatures

Maria
Python
15 Sep, 2026

You've seen def wrapper(*args, **kwargs): in decorators, and probably super().__init__(**kwargs) in class hierarchies. These two parameters let a

Python Scope Explained: LEGB, global, and nonlocal

Maria
Python
15 Sep, 2026

Every time Python sees a name like count or len, it has to figure out which variable that name refers to. Most of the time the answer is obvious

Structural Pattern Matching in Python with match and case

Maria
Python
15 Sep, 2026

Python 3.10 added the match statement, and many developers filed it away as "Python finally got switch". That undersells it. match can compare

The Walrus Operator (:=) in Python: When It Helps and When It Hurts

Maria
Python
15 Sep, 2026

The walrus operator, :=, landed in Python 3.8 after one of the most heated debates in the language's history. Its official name is the **assignment

Unpacking in Python: Starred Expressions, Swaps, and Multiple Assignment

Maria
Python
15 Sep, 2026

Unpacking is one of those Python features you use long before you know its name. for key, value in d.items(): is unpacking. So is x, y = point, a

List, Dict, and Set Comprehensions in Python: Writing Cleaner Loops

Maria
Python
14 Sep, 2026

A large share of the loops in any Python codebase do the same thing: start with an empty list or dict, loop over something, maybe skip a few items, a

f-Strings in Python: Formatting Tricks You Probably Aren't Using

Maria
Python
14 Sep, 2026

Most Python developers use f-strings every day, but usually only for the simplest job: dropping a variable into a string. f"Hello, {name}" is nice,

Understanding Python's Truthiness: How if Decides What's True

Maria
Python
14 Sep, 2026

In Python you can write if items: instead of if len(items) > 0:, and if name: instead of if name != "":. The condition in an if doesn't hav

Python Variables and Mutability: Why Lists Change and Strings Don't

Maria
Python
14 Sep, 2026

Sooner or later every Python developer hits this: you copy a list into a new variable, change the "copy", and the original changes too. Then you try

What is a Generator in Python? How is it Different from a Regular Function?

Maria
Python
04 Aug, 2024

Generators are a powerful feature in Python that allow for efficient iterat

How to debug a Python program?

Maria
Python
30 May, 2024

Debugging is a crucial part of the development process. It helps you find and fix errors in your code, ensuring that your program runs correctly. Pyt

How to use the init method?

Maria
Python
29 May, 2024

In the realm of object-oriented programming, the init method plays a crucial role in the initialization process of objects. It is a special method th

What is PIP and How Do I Use It?

Maria
Python
28 May, 2024

PIP (Pip Installs Packages) is the standard package management system for Python. It ena

How to Convert Between Data Types in Python ?

Maria
Python
27 May, 2024

Python is a dynamically typed language, meaning that variables can change data types as needed. However, sometimes it'

What are Python Modules and Packages?

Maria
Python
26 May, 2024

Python modules and packages are fundamental tools that help in organizing and structuring Python code. They enable code re

Python's Best Practices for Coding

Maria
Python
25 May, 2024

Writing clean, readable, and maintainable code is crucial for any successful software project. Python, with its emphasis on readability and simplicit

What are Python's Main Features?

Maria
Python
25 May, 2024

Python is a powerful and versatile programming language that is widely used across various domains. Its design philosophy

What is the difference between Python 2 and Python 3?

Maria
Python
24 May, 2024

Python is a versatile programming language that has undergone significant changes over the years. The most notable of

How to use Python with databases?

Maria
Python
04 May, 2024

Python is a versatile language that is often used for backend development, data analysis, and scripting. One of its powerful c

How to Use Python for Data Analysis?

Maria
Python
02 May, 2024

Python has become a dominant language in the field of data analysis due to its simplicity, readability, and extensive ecosystem of powerful libraries