Leanpub Header

Skip to main content

The Complete Python Developer

From First Steps to Professional Development

This book is 100% completeLast updated on 2026-07-30

Whether you're writing your first line of code or building professional applications, this book takes you from the fundamentals to real world Python development. Learn the skills, tools and best practices used by experienced developers to write clean, reliable and scalable code with confidence.

Minimum price

$19.00

$29.00

You pay

Author earns

$

Also available for 1 book credit with a Reader Membership

PDF
EPUB
WEB
APP
273
Pages
About

About

About the Book

Python is one of the most widely used programming languages in the world, powering everything from web applications and data pipelines to artificial intelligence systems and scientific research. Its clarity, versatility, and massive ecosystem make it an ideal first language for beginners and a daily tool for seasoned professionals. Yet mastering Python means more than memorizing syntax; it requires understanding modern practices, tooling, and patterns that separate hobbyist scripts from production-grade software.

Bundles

Bundles that include this book

Author

About the Author

Steve Publications

Steve is a technology professional with more than 20 years of experience in software development, server infrastructure, cybersecurity, vulnerability research and reverse engineering. Throughout his career, he has designed, secured, analyzed and tested complex software and infrastructure, with a particular focus on understanding how systems fail and how they can be made more secure.

Outside of work, Steve enjoys sharing knowledge with the technology community. He collaborates with researchers, industry experts and technology professionals to write practical books covering software development, cybersecurity, cloud computing, networking, DevOps, artificial intelligence and enterprise technologies. His books focus on practical learning through clear explanations, real-world examples and hands-on exercises. With more than two decades of industry experience, his goal is to help IT professionals, students and technology enthusiasts build useful skills and stay current in a rapidly changing industry.

We believe readers deserve to know how our books are created. Most of our authors are not native English speakers, so we use AI to help translate, proofread manuscripts, fix grammar, improve sentence structure and make technical explanations easier to read. AI is used as an editing tool only. It does not replace the research, technical knowledge or hands-on experience behind our books. Some of our authors also prefer to remain anonymous for privacy or professional reasons. In those cases, we publish their work under a different name. The author's name may be different, but the quality of the content and our review process remain the same.

Every book is written, reviewed and maintained by experienced technology professionals, with contributions from our private technical community of more than 420 engineers and researchers from Ukraine, Belarus and Russia. We spend far more time validating technical accuracy and keeping our content up to date than generating text. We are always interested in working with experienced professionals who have deep expertise in a particular technology or domain. If you would like to publish a book with us or help review an existing manuscript, we'd love to hear from you. Send us a message describing your area of expertise. We are especially interested in niche technologies, specialized skills and emerging topics that are underrepresented in existing technical literature.

If you look through the contents of our books, you'll see practical examples, detailed explanations and material that is regularly updated. Our goal is to publish books that professionals can actually rely on, not low-effort AI-generated content. If you ever feel that one of our books does not meet that standard, Leanpub offers a 60-day money-back guarantee. Feel free to request a refund if you are not satisfied with your purchase.

Contents

Table of Contents

From First Steps to Professional Development

Introduction: Why Python, and Where to Start

  1. What This Book Will Do for You
  2. How to Read This Book
  3. A Note on Learning

Chapter 1: Welcome to Python, Your First Steps

  1. Why Python Matters Today
  2. Installing Python and Verifying Your Setup
  3. Running Python: The Interactive Shell and Scripts
  4. Understanding Errors Before You Fear Them
  5. Choosing an Editor or IDE
  6. Your First Development Workflow
  7. Chapter Summary

Chapter 2: The Building Blocks: Variables, Types, and Operations

  1. Variables and Names: How Python Stores Values
  2. Numbers: Integers, Floats, and Complex Numbers
  3. Strings: Text, Formatting, and Manipulation
  4. Booleans and Comparison Operators
  5. Type Conversion and Dynamic Typing
  6. Arithmetic, Logical, and Bitwise Operations
  7. Building a Small Example: A Unit Converter
  8. Chapter Summary

Chapter 3: Controlling the Flow: Decisions, Loops, and Patterns

  1. Conditional Logic with if, elif, and else
  2. While Loops: Repeating Until a Condition Changes
  3. For Loops: Iterating Over Sequences
  4. List, Dict, and Set Comprehensions
  5. Structural Pattern Matching with match and case
  6. Breaking, Continuing, and Nesting Control Structures
  7. Building a Small Example: A Task Manager Prototype
  8. Chapter Summary

Chapter 4: Functions: Building Reusable Code

  1. Defining and Calling Functions
  2. Parameters, Arguments, and Default Values
  3. Return Values and Multiple Returns
  4. Variable Scope and the LEGB Rule
  5. *args and **kwargs: Flexible Function Signatures
  6. Docstrings and Documenting Your Code
  7. Type Hints on Functions
  8. Refactoring the Task Manager with Functions
  9. Chapter Summary

Chapter 5: Data Structures: Organizing Information

  1. Lists: Ordered, Mutable Sequences
  2. Tuples: Immutable Records and Multiple Return Values
  3. Dictionaries: Key-Value Mappings
  4. Sets: Unordered Collections of Unique Items
  5. The collections Module: Specialized Data Structures
  6. Choosing the Right Structure for the Job
  7. Building a Better Task Manager Data Model
  8. Chapter Summary

Chapter 6: Modules, Packages, and Project Organization

  1. Creating and Importing Modules
  2. Understanding the Import System
  3. Building Packages with init.py
  4. Project Layout Patterns for Real Applications
  5. The Standard Library: Your First Stop for Solutions
  6. Restructuring the Task Manager as a Package
  7. Chapter Summary

Chapter 7: Object-Oriented Programming: Designing with Classes

  1. Classes and Instances: The Basics
  2. Methods, Attributes, and self
  3. Inheritance and Method Resolution Order
  4. Polymorphism and Duck Typing
  5. Encapsulation, Properties, and Name Mangling
  6. Dataclasses and Modern Class Design
  7. Special Methods: init, str, repr, and Friends
  8. Chapter Summary

Chapter 8: Error Handling, Logging, and Testing

  1. Exceptions: Catching and Raising Errors Gracefully
  2. Custom Exception Classes for Domain Clarity
  3. The try/except/finally Pattern in Practice
  4. Logging: Beyond print() to Production Diagnostics
  5. Writing Tests with pytest
  6. Interactive Debugging with pdb and ipdb
  7. Chapter Summary

Chapter 9: File I/O, Serialization, and Working with Data

  1. Opening and Closing Files Safely
  2. Reading and Writing Text Files
  3. The pathlib Module for Modern Path Handling
  4. Working with JSON Data
  5. CSV and Tabular Data Processing
  6. Binary Files and Serialization with pickle
  7. Building Persistent Storage for the Task Manager
  8. Chapter Summary

Chapter 10: Functional Programming and Advanced Patterns

  1. First-Class Functions and Higher-Order Functions
  2. Lambda Expressions and Functional Tools
  3. Iterators and the Iterator Protocol
  4. Generators and Lazy Evaluation
  5. Context Managers and the with Statement
  6. Chapter Summary

Chapter 11: Concurrency and Asynchronous Programming

  1. The Global Interpreter Lock and Its Implications
  2. Threading for I/O-Bound Tasks
  3. Multiprocessing for CPU-Bound Work
  4. Asyncio: Cooperative Concurrency with async and await
  5. Building Asynchronous Applications End-to-End
  6. Choosing the Right Concurrency Model
  7. Chapter Summary

Chapter 12: Networking, APIs, and Web Development

  1. HTTP Fundamentals for Python Developers
  2. Making HTTP Requests with the requests Library
  3. Building a REST API with FastAPI
  4. Handling Authentication and API Keys
  5. Web Scraping and Data Extraction Basics
  6. Deploying Your First Web Application
  7. Chapter Summary

Chapter 13: Databases and Data Persistence

  1. Relational Database Fundamentals
  2. Using SQLite with the sqlite3 Module
  3. SQLAlchemy: The Pythonic Database Toolkit
  4. Database Migrations with Alembic
  5. Data Modeling and Schema Design Patterns
  6. Integrating the Task Manager with a Database
  7. Database Performance: Connection Pooling and Query Optimization
  8. Chapter Summary

Chapter 14: Type System, Code Quality, and Modern Tooling

  1. Python Type Hints and the typing Module
  2. Static Type Checking with mypy
  3. Code Formatting with Black and Sorting Imports
  4. Linting and Analysis with Ruff and flake8
  5. Pre-commit Hooks for Automated Quality Gates
  6. Integrating Tools into Your Workflow
  7. Generating Project Documentation with Sphinx and MkDocs
  8. Usage
  9. Chapter Summary

Chapter 15: Packaging, Deployment, and the Professional Workflow

  1. Virtual Environments and Dependency Isolation
  2. pyproject.toml and Modern Build Systems
  3. Publishing Packages to PyPI
  4. Containerization with Docker for Python Apps
  5. CI/CD Pipelines for Python Projects
  6. Security Best Practices for Python Applications
  7. Chapter Summary

Chapter 16: Profiling and Performance Optimization

  1. The Performance Workflow: Measure Before You Optimize
  2. CPU Profiling with cProfile
  3. Line-Level Profiling with line_profiler
  4. Memory Profiling with memory_profiler
  5. Statistical Profiling with Pyinstrument
  6. Algorithmic Complexity and Big-O Notation
  7. Practical Optimization Techniques
  8. Advanced Optimization: Cython, PyPy, and Vectorization
  9. When to Stop Optimizing
  10. Chapter Summary

Chapter 17: Design Patterns for Python

  1. The Guiding Principle: Simple First
  2. Creational Patterns: Controlling Object Creation
  3. Structural Patterns: Organizing Relationships
  4. Behavioral Patterns: Managing Communication and Logic
  5. When Patterns Help and When They Hurt
  6. Chapter Summary

Chapter 18: Data Processing, Scientific Computing, and the AI/ML Ecosystem

  1. Why Python Dominates Data Science
  2. NumPy: The Foundation of Numerical Python
  3. pandas: Data Manipulation and Analysis
  4. Data Processing Workflow: End-to-End Example
  5. The Machine Learning Ecosystem Overview
  6. Jupyter Notebooks for Interactive Exploration
  7. Chapter Summary

Conclusion: Your Path Forward as a Python Developer

References

Get the free sample chapters

Click the buttons to get the free sample in PDF or EPUB, or read the sample online here

The Leanpub 60 Day 100% Happiness Guarantee

Within 60 days of purchase you can get a 100% refund on any Leanpub purchase, in two clicks.

See full terms...

Earn $8 on a $10 Purchase, and $16 on a $20 Purchase

We pay 80% royalties on purchases of $7.99 or more, and 80% royalties minus a 50 cent flat fee on purchases between $0.99 and $7.98. You earn $8 on a $10 sale, and $16 on a $20 sale. So, if we sell 5000 non-refunded copies of your book for $20, you'll earn $80,000.

(Yes, some authors have already earned much more than that on Leanpub.)

In fact, authors have earned over $15 million writing, publishing and selling on Leanpub.

Learn more about writing on Leanpub

Free Updates. DRM Free.

If you buy a Leanpub book, you get free updates for as long as the author updates the book! Many authors use Leanpub to publish their books in-progress, while they are writing them. All readers get free updates, regardless of when they bought the book or how much they paid (including free).

Most Leanpub books are available in PDF (for computers) and EPUB (for phones, tablets and Kindle). The formats that a book includes are shown at the top right corner of this page.

Finally, Leanpub books don't have any DRM copy-protection nonsense, so you can easily read them on any supported device.

Learn more about Leanpub's ebook formats and where to read them

Write and Publish on Leanpub

You can use Leanpub to easily write, publish and sell in-progress and completed ebooks and online courses!

Leanpub is a powerful platform for serious authors, combining a simple, elegant writing and publishing workflow with a store focused on selling in-progress ebooks.

Leanpub is a magical typewriter for authors: just write in plain text, and to publish your ebook, just click a button. (Or, if you are producing your ebook your own way, you can even upload your own PDF and/or EPUB files and then publish with one click!) It really is that easy.

Learn more about writing on Leanpub