Leodanis Pozo Ramos — Python Educator

Core Real Python team · since 2020

Leodanis is a self-taught Python developer, educator, and technical writer with over 10 years of experience. After earning a master’s degree in Quality Assurance and spending about a decade as a machinery lubrication engineer, he pivoted to Python programming.

At Real Python, Leodanis creates in-depth Python tutorials covering core language features, GUI programming, and command-line interface (CLI) development. His example-driven style has helped many Python learners level up their coding skills.

Leodanis has also published expert-level articles for leading programming sites, including PythonGUIs.com and StackAbuse.com. He is passionate about making complex topics approachable for new developers and advocating best practices in Python.

Tutorials by Leodanis:

• Defining Your Own Python Function
• Control Flow Structures in Python
• Sets in Python
• Managing Python Projects With uv: An All-in-One Solution
• Namespaces in Python
• Using Python's .__dict__ to Work With Attributes
• Python Code Quality: Best Practices and Tools
• Python News Roundup: March 2025
• Python while Loops: Repeating Tasks Conditionally
• Python for Loops: The Pythonic Way
• Build a Dice-Rolling Application With Python
• Build a Tic-Tac-Toe Game With Python and Tkinter
• Providing Multiple Constructors in Your Python Classes
• A Guide to Modern Python String Formatting Tools
• Lists vs Tuples in Python
• Python's zipfile: Manipulate Your ZIP Files Efficiently
• Python's Mutable vs Immutable Types: What's the Difference?
• Python's "in" and "not in" Operators: Check for Membership
• Python's raise: Effectively Raising Exceptions in Your Code
• Getters and Setters: Manage Attributes in Python
• Python Class Constructors: Control Your Object Instantiation
• Python Constants: Improve Your Code's Maintainability
• How to Install Python on Your System: A Guide
• Python's min() and max(): Find Smallest and Largest Values
• Python's assert: Debug and Test Your Code Like a Pro
• Variables in Python: Usage and Best Practices
• Operators and Expressions in Python
• Iterators and Iterables in Python: Run Efficient Iterations
• Strings and Character Data in Python
• How to Flatten a List of Lists in Python
• Basic Data Types in Python: A Quick Exploration
• Dictionaries in Python
• Build Enumerations of Constants With Python's Enum
• Python's property(): Add Managed Attributes to Your Classes
• Python Classes: The Power of Object-Oriented Programming
• Build Command-Line Interfaces With Python's argparse
• Python Set Comprehensions: How and When to Use Them
• Using and Creating Global Variables in Your Python Functions
• How to Run Your Python Scripts and Code
• Python String Formatting: Available Tools and Their Features
• Efficient String Concatenation in Python
• How to Iterate Through a Dictionary in Python
• Using the Python zip() Function for Parallel Iteration
• Python Dictionary Comprehensions: How and When to Use Them
• Python Closures: Common Use Cases and Examples
• Syntactic Sugar: Why Python Is Sweet and Pythonic
• Build a Contact Book App With Python, Textual, and SQLite
• Python News Roundup: August 2024
• Asynchronous Iterators and Iterables in Python
• Python Protocols: Leveraging Structural Subtyping
• Python's Built-in Functions: A Complete Exploration
• Creating Great README Files for Your Python Projects
• String Interpolation in Python: Exploring Available Tools
• Python's Built-in Exceptions: A Walkthrough With Examples
• Python News: What's New From April 2024
• Python's unittest: Writing Unit Tests for Your Code
• Write Unit Tests for Your Python Code With ChatGPT
• Python's __all__: Packages, Modules, and Wildcard Imports
• Duck Typing in Python: Writing Flexible and Decoupled Code
• BNF Notation: Dive Deeper Into Python's Grammar
• Python News: What's New From January 2024
• Python's Format Mini-Language for Tidy Strings
• Python's Magic Methods: Leverage Their Power in Your Classes
• Build a Hangman Game With Python and PySimpleGUI
• Single and Double Underscores in Python Names
• Build Conway's Game of Life With Python
• Document Your Python Code and Projects With ChatGPT
• Python's tuple Data Type: A Deep Dive With Examples
• Python News: What's New From August 2023
• Click and Python: Build Extensible and Composable CLI Apps
• Python 3.12 Preview: More Intuitive and Consistent F-Strings
• Python's list Data Type: A Deep Dive With Examples
• Python's .__call__() Method: Creating Callable Instances
• SOLID Principles: Improve Object-Oriented Design in Python
• Python News: What's New From March 2023
• Python's del: Remove References From Scopes and Containers
• The Python Standard REPL: Try Out Code and Ideas Quickly
• Python's Assignment Operator: Write Robust Assignments
• Python's doctest: Document and Test Your Code at Once
• Python News: What's New From September 2022
• Custom Python Strings: Inheriting From str vs UserString
• Custom Python Lists: Inheriting From list vs UserList
• Python and PyQt: Building a GUI Desktop Calculator
• Python's exec(): Execute Dynamically Generated Code
• Custom Python Dictionaries: Inheriting From dict vs UserDict
• How Can You Emulate Do-While Loops in Python?
• LBYL vs EAFP: Preventing or Handling Errors in Python
• Python News: What's New From March 2022
• Build a Site Connectivity Checker in Python
• Python's all(): Check Your Iterables for Truthiness
• Python Zip Imports: Distribute Modules and Packages Quickly
• Build a Command-Line To-Do App With Python and Typer
• Python's zipapp: Build Executable Zip Applications
• Using the "not" Boolean Operator in Python
• Python's sum(): The Pythonic Way to Sum Values
• Reverse Strings in Python: reversed(), Slicing, and More
• Using the "and" Boolean Operator in Python
• Python's deque: Implement Efficient Queues and Stacks
• Python's ChainMap: Manage Multiple Contexts Effectively
• Python's collections: A Buffet of Specialized Data Types
• What Can I Do With Python?
• Python's Counter: The Pythonic Way to Count Objects
• Reverse Python Lists: Beyond .reverse() and reversed()
• Python's filter(): Extract Values From Iterables
• Context Managers and Python's with Statement
• Build a Bulk File Rename Tool With Python and PyQt
• Write Pythonic and Clean Code With namedtuple
• Build a Python Directory Tree Generator for the Command Line
• OrderedDict vs dict in Python: The Right Tool for the Job
• Build a Contact Book With Python, PyQt, and SQLite
• Python and MongoDB: Connecting to NoSQL Databases
• Python Inner Functions: What Are They Good For?
• Qt Designer and Python: Build Your GUI Applications Faster
• How to Use Python: Your First Steps
• Python's .append(): Add Items to Your Lists in Place
• Use PyQt's QThread to Prevent Freezing GUIs
• Handling SQL Databases With PyQt: The Basics
• PyQt Layouts: Create Professional-Looking GUI Applications
• Python and PyQt: Creating Menus, Toolbars, and Status Bars
• Python's map(): Processing Iterables Without a Loop
• The Python return Statement: Usage and Best Practices
• Python's reduce(): From Functional to Pythonic Style
• Python eval(): Evaluate Expressions Dynamically
• Python Scope & the LEGB Rule: Resolving Names in Your Code
• Using the Python defaultdict Type for Handling Missing Keys
• Using the "or" Boolean Operator in Python

Tutorials Leodanis Contributed to:

• Python's Bytearray: A Mutable Sequence of Bytes
• Python Textual: Build Beautiful UIs in the Terminal
• Bytes Objects: Handling Binary Data in Python
• Create and Modify PDF Files in Python
• How to Get a List of All Files in a Directory With Python
• How to Remove Items From Lists in Python
• Using Python's pip to Manage Your Projects' Dependencies
• YAML: The Missing Battery in Python
• Python's F-String for String Interpolation and Formatting
• Python range(): Represent Numerical Ranges
• Using the len() Function in Python
• Model-View-Controller (MVC) in Python Web Apps: Explained With Lego
• Python's Array: Working With Numeric Data Efficiently
• Build a Hangman Game for the Command Line in Python
• Build a Code Image Generator With Python
• Use ChatGPT to Learn Python Programming
• When Should You Use .__repr__() vs .__str__() in Python?
• Discover bpython: A Python REPL With IDE-Like Features
• Build Your Python Project Documentation With MkDocs
• Build a Hash Table in Python With TDD
• Python 3.11 Preview: Even Better Error Messages
• Raining Outside? Build a Weather CLI App With Python
• A Python Guide to the Fibonacci Sequence
• How Long Does It Take to Learn Python?
• Using Python Optional Arguments When Defining Functions
• Python and REST APIs: Interacting With Web Services
• Python Practice Problems: Parsing CSV Files
• The LEGB Rule & Understanding Python Scope (Course)
• Creating a Python Dice Roll Application (Course)
• Checking for Membership Using Python's "in" and "not in" Operators (Course)
• What Can You Do With Python? (Course)
• Getting to Know Duck Typing in Python (Course)
• Single and Double Underscore Naming Conventions in Python (Course)
• Concatenating Strings in Python Efficiently (Course)
• Building a Python Command-Line To-Do App With Typer (Course)
• Exploring Python's tuple Data Type With Examples (Course)
• Building Dictionary Comprehensions in Python (Course)
• Handling or Preventing Errors in Python: LBYL vs EAFP (Course)
• Python's Magic Methods in Classes (Course)
• Differences Between Python's Mutable and Immutable Types (Course)
• Defining Python Constants for Code Maintainability (Course)
• Build a GUI Calculator With PyQt and Python (Course)
• Efficient Iterations With Python Iterators and Iterables (Course)
• Flattening a List of Lists in Python (Course)
• Working With Global Variables in Python Functions (Course)
• Using raise for Effective Exceptions (Course)
• Create Conway's Game of Life With Python (Course)
• Building Enumerations With Python's enum (Course)
• Using Python's min() and max() (Course)
• Design and Guidance: Object-Oriented Programming in Python (Course)
• Inheritance and Internals: Object-Oriented Programming in Python (Course)
• Class Concepts: Object-Oriented Programming in Python (Course)
• Reversing Strings in Python (Course)
• Filtering Iterables With Python (Course)
• Getting the Most Out of the Python Standard REPL (Course)
• Using Python's assert to Debug and Test Your Code (Course)
• Using OrderedDict in Python (Course)
• Summing Values the Pythonic Way With sum() (Course)
• Manipulating ZIP Files With Python (Course)
• Writing Clean, Pythonic Code With namedtuple (Course)
• Getters and Setters in Python (Course)
• Context Managers and Using Python's with Statement (Course)
• Using Multiple Constructors in Your Python Classes (Course)
• Building Command Line Interfaces With argparse (Course)
• Managing Attributes With Python's property() (Course)
• Using the Python not Operator (Course)
• Using the Python and Operator (Course)
• Building a Site Connectivity Checker (Course)
• Using Python Class Constructors (Course)
• Counting With Python's Counter (Course)
• Building Lists With Python's .append() (Course)
• Using the Python return Statement Effectively (Course)
• Defining and Calling Python Functions (Course)
• Python Inner Functions (Course)
• Python Basics: Setting Up Python (Course)
• Using the Python or Operator (Course)
• Python's map() Function: Transforming Iterables (Course)
• Navigating Namespaces and Scope in Python (Course)
• Creating PyQt Layouts for GUI Applications (Course)
• Evaluate Expressions Dynamically With Python eval() (Course)
• Formatting Python Strings (Course)
• Handling Missing Keys With the Python defaultdict Type (Course)
• Parallel Iteration With Python's zip() Function (Course)
• Using Sets in Python (Course)
• Exploring Basic Data Types in Python (Course)
• Python Dictionary Iteration: Advanced Tips & Tricks (Course)
• Variables in Python (Course)
• Strings and Character Data in Python (Course)
• Lists and Tuples in Python (Course)
• Using Dictionaries in Python (Course)
• Installing Python on Windows, macOS, and Linux (Course)
• Python String Formatting Tips & Best Practices (Course)
• Running Python Scripts (Course)
• For Loops in Python (Definite Iteration) (Course)
• Mastering While Loops (Course)