Python Learning

7 GitHub repositories that will help you become a great Python developer 1. Python Project Based Learning • Curated list of project based tutorials • 284k stars • Webapps, web scraping, bots, data science, ML, and more. 2. All algorithms implemented in Python • Boatloads of algorithms implemented in Python • 225k stars • Algorithms neatly categorized 3. 30 Days of Python • Step-by-step guide to learn the Python • 74k stars • Logical learning sequence, great explanations and helpful getting started guide 4. 100-Days-Of-ML-Code • A great resource for learning ML • 52k stars • High quality infographic explanations 5. Playground and Cheatsheet for Learning Python • Collection of Python scripts that are split by topics and contain code examples with explanations. • 18k stars • Explanations next to the code make it easy to learn 6. Practical Python Programming • Designed for people that have some programming experience but don’t know Python yet • 11k stars • Course has it’s own easy to use site 7. Python Programming Exercises • 100+ Python challenging programming exercises • 29k stars • Questions, hints, solutions. Simple and effective way to practice. 👉 Keep Learning and Building!

📖 Applied Machine Learning in Python If you are getting started with MachineLearning or if you are an expert seeking a practical resource to refine your skills this e-book is for you. ✅ What you'll find inside: 1. Clear explanations of theory 2. Best practices for applied machine learning 3. Step-by-step demonstrations in Jupyter Notebooks 🔗 You Can Read it Here

Python for Software Engineering Roadmap (2026) 1️⃣ PYTHON FUNDAMENTALS 2️⃣ DATA STRUCTURES & ALGORITHMS 3️⃣ SOFTWARE DEVELOPMENT PRACTICES 4️⃣ BACKEND DEVELOPMENT 5️⃣ DATABASES 6️⃣ TESTING 7️⃣ FRONTEND BASICS 8️⃣ SECURITY 9️⃣ DEVOPS & DEPLOYMENT 🔟 SYSTEM DESIGN

📌 The most comprehensive Python cheat sheet! And it's free on GitHub Basic datatypes, Generators & decorators, ALL important core modules, Threading, JSON & CSV, OOP, Typing, Logging, Exceptions, OS commands and soo much more! 👉 Comprehensive Python Cheatsheet

📘 The Big Book of Small Python Projects ✍️ Author: Al Sweigart 🔗 Read Online #Python #Projects ➖➖➖➖➖➖➖➖➖➖➖ 📚 More free programming books → @free_programming_books_bds Part of @bigdataspecialist community

🐛 This Python Bug Looks Random, But It Isn't Look at this:

functions = []

for i in range(3):
    functions.append(lambda: i)

for f in functions:
    print(f())

What would you expect?

0
1
2

Actual output:

2
2
2

Why? The lambdas don't store the current value of i. They remember the variable i. By the time the functions are called, the loop has finished and i is 2. This is called late binding. If you actually want each function to capture the current value:

functions = []

for i in range(3):
    functions.append(lambda i=i: i)

Now:

0
1
2

This becomes particularly important when creating callbacks inside loops, especially in GUI code, asynchronous code, and event-driven applications. The bug isn't in lambda. It's in understanding when the variable is looked up.

🐍 Python Performance Optimization Python Performance Optimization: Make Your Code Faster Writing Python code that works is only the beginning. For real-world applications, performance matters. Here are some techniques that can significantly improve Python performance: ⚡️ 1. Use the right data structures Choosing a set instead of a list for frequent membership checks can dramatically reduce lookup time. ⚡️ 2. Avoid unnecessary loops Use built-in functions, comprehensions, and optimized libraries such as NumPy when appropriate. ⚡️ 3. Profile before optimizing Tools like cProfile and timeit help identify the actual bottlenecks instead of optimizing blindly. ⚡️ 4. Reduce unnecessary memory usage Generators can process large datasets without loading everything into memory at once. ⚡️ 5. Use vectorization for data processing NumPy operations can be much faster than manually looping through millions of values. 💡 Key principle: Don't optimize what you haven't measured.

🐍 Python Beginner Notes

🧠 return vs print() in Python These are not interchangeable.

def add(a, b):
    print(a + b)

Calling:

result = add(2, 3)

prints:

5

But:

result

is actually:

None

Now compare:

def add(a, b):
    return a + b

This time:

result = add(2, 3)

gives:

result == 5

print() sends something to the screen. return sends a value back to the caller. That distinction becomes extremely important once functions start calling other functions.

PYTHON SKILL ROADMAP │ ├── 📁 Python Basics │ ├── 📁 Variables & Data Types │ ├── 📁 Input & Output │ ├── 📁 Operators │ ├── 📁 Conditional Statements │ └── 📁 Loops │ ├── 📁 Core Python Concepts │ ├── 📁 Lists │ ├── 📁 Tuples │ ├── 📁 Sets │ ├── 📁 Dictionaries │ ├── 📁 Strings │ └── 📁 Functions │ ├── 📁 Problem Solving │ ├── 📁 Patterns │ ├── 📁 Number Problems │ ├── 📁 String Problems │ ├── 📁 List Problems │ ├── 📁 Searching │ └── 📁 Sorting Basics │ ├── 📁 Object-Oriented Python │ ├── 📁 Classes & Objects │ ├── 📁 Constructors │ ├── 📁 Inheritance │ ├── 📁 Encapsulation │ ├── 📁 Polymorphism │ └── 📁 Real OOP Examples │ ├── 📁 File Handling & Errors │ ├── 📁 Read Files │ ├── 📁 Write Files │ ├── 📁 CSV Files │ ├── 📁 JSON Files │ ├── 📁 Exception Handling │ └── 📁 Logging Basics │ ├── 📁 Python Libraries │ ├── 📁 NumPy Basics │ ├── 📁 Pandas Basics │ ├── 📁 Matplotlib Basics │ ├── 📁 Requests │ ├── 📁 BeautifulSoup │ └── 📁 Streamlit Basics │ ├── 📁 Automation Skills │ ├── 📁 File Organizer │ ├── 📁 Email Automation │ ├── 📁 Web Scraping │ ├── 📁 API Automation │ ├── 📁 Excel Automation │ └── 📁 Task Scheduler │ ├── 📁 Backend Basics │ ├── 📁 Flask Basics │ ├── 📁 FastAPI Basics │ ├── 📁 REST APIs │ ├── 📁 Databases │ ├── 📁 Authentication Basics │ └── 📁 Deploy Your API │ └── 📁 Portfolio Projects ├── 📁 Expense Tracker ├── 📁 Weather App ├── 📁 Web Scraper ├── 📁 URL Shortener ├── 📁 Automation Bot └── 📁 AI Note Summarizer Learn the syntax first. Then solve problems. Then build projects. That is how Python starts making sense. @python_bds

The tell() function in Python 🐍 The tell() function returns the current position of the file pointer within the data stream. It is most often used when working with files. 📂 The function does not accept any arguments and returns an integer - the position in bytes from the beginning of the stream. 🔢

with open("file.txt", "rb") as f:
    print(f.tell())

25 Github Repositories Every Python Developer Should Know 1. Python The official repository of Python's source code. Dive into it to explore Python's internals or contribute to the language's development. 2. Awesome Python A curated list of awesome Python frameworks, libraries, software, and resources. A perfect starting point for any Python developer. 3. Requests Simplifies HTTP requests in Python. A must-have library for working with APIs and web scraping. 4. Flask A lightweight web framework that is simple to use yet highly flexible, ideal for small to medium-sized applications. 5. Django A high-level web framework that encourages rapid development and clean, pragmatic design for building robust web applications. 6. FastAPI A modern web framework for building APIs with Python. Known for its speed and automatic OpenAPI documentation. 7. Pandas Provides powerful tools for data manipulation and analysis, including support for data frames. 8. NumPy The go-to library for numerical computations. It’s the backbone of Python’s scientific computing stack. 9. Matplotlib A plotting library for creating static, animated, and interactive visualizations in Python. 10. Seaborn Builds on Matplotlib and simplifies creating beautiful and informative statistical graphics. 11. Scikit-learn A machine learning library featuring various classification, regression, and clustering algorithms. 12. TensorFlow A powerful framework for machine learning and deep learning, supported by Google. 13. PyTorch Another leading machine learning framework, known for its flexibility and dynamic computation graph. 14. BeautifulSoup Simplifies web scraping by parsing HTML and XML documents. 15. Scrapy An advanced web scraping and web crawling framework. 16. Streamlit Makes it easy to build and share data apps using pure Python. Great for data scientists. 17. Celery A distributed task queue library for running asynchronous jobs. 18. SQLAlchemy A powerful ORM (Object-Relational Mapping) tool for managing database operations in Python. 19. Pytest A robust testing framework for writing simple and scalable test cases. 20. Black An uncompromising code formatter for Python. Makes your code consistent and clean. 21. Bokeh For creating interactive visualizations in modern web browsers. 22. Plotly Another library for creating interactive visualizations but with more customization options. 23. OpenCV The go-to library for computer vision tasks like image processing and object detection. 24. Pillow A friendly fork of PIL (Python Imaging Library), used for image processing tasks. 25. Rich A Python library for beautiful terminal outputs with rich text, progress bars, and more.

⚡️ Python’s 1-Line Speed Booster: @lru_cache 👉 Did you know you can make slow Python functions run up to 100x faster by adding a single line of code? Most tutorials skip functools.lru_cache, but it’s one of Python’s best built-in performance hacks. 🔹 How It Works It automatically caches (remembers) the results of function calls. If you call the function with the same inputs again, Python skips the heavy computation and returns the saved answer instantly. 🔹 Code Comparison ❌ Slow (Re-calculates every single call):

def get_user_data(user_id):
    # Imagine an expensive database query here
    return fetch_from_db(user_id)

✅ Very Fast (Remembers previous results):

from functools import lru_cache


@lru_cache(maxsize=128)
def get_user_data(user_id):
    # Only runs ONCE per unique user_id
    return fetch_from_db(user_id)

🔹 Use It to: ✔️ Speedup repetitive API calls, math calculations, or DB queries. ✔️ No third-party libraries needed (built into Python's standard library). ✔️ Prevent unnecessary server load.