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Python Coding
Challenges

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467 challenges 330 easy 120 medium 17 hard

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All Python Basics Strings & Text Lists & Arrays Dicts & Sets Functions & Closures OOP & Classes Data Structures & Algorithms Advanced Python Iterators & Generators Decorators & Context Managers Error Handling & Exceptions Regular Expressions Math & Number Theory Bit Manipulation Dynamic Programming Trees & Binary Trees Graphs & Graph Algorithms Recursion & Backtracking Greedy Algorithms Binary Search Two Pointers & Sliding Window Stacks & Queues Heaps & Priority Queues Linked Lists Matrix & 2D Arrays Datetime & Time Calculations Data Formats & Parsing SQL & SQLite Numpy & Vectorized Computing Cryptography & Hashing

Functions & Closures medium

Memoize decorator

Implement a @memoize decorator that caches results of a function.

decorators closures caching

Functions & Closures medium

Function composition

Return a function that applies f after g: compose(f, g)(x) == f(g(x)).

functional closures higher-order

Functions & Closures hard

Curry a function

Auto-curry any multi-argument function so it returns partial applications until fully saturated.

functional closures inspect

Functions & Closures easy

Bind First Argument

Implement bind_first_arg, a decorator that fixes the first argument of any function.

decorators closures functions

Decorators & Context Managers easy

Once Decorator: Run a Function Only Once

Implement a decorator that caches and returns the result of the first call for subsequent calls.

decorators closures caching

Decorators & Context Managers medium

Memoize with TTL

Implement a decorator that caches function results for a limited time, returning cached values within the TTL and recomputing after expiry.

decorators memoization caching

Decorators & Context Managers medium

LRU Memoize

Implement an LRU memoization decorator that caches results for a fixed number of arguments.

decorators caching lru

Decorators & Context Managers medium

Rate Limit Decorator

Implement a decorator that enforces a maximum number of calls per second for any function.

decorator time rate-limiting

Decorators & Context Managers medium

Profile time decorator

Create a decorator that tracks how many times a function is called and its cumulative execution time.

decorators timing profiling

Showing 9 challenges

Guide: free Python coding challenges

Practice Python by solving problems

PythonSkillset challenges are hands-on coding exercises from beginner to advanced. Open a challenge, read the problem, write Python in the split-pane editor, and run tests with Pyodide — no install required.

How to use the arena

Pick a category — basics, algorithms, strings, and more
Open a challenge, read the statement, and edit the starter code
Run tests, fix failures, then try a related quiz or tutorial lesson

Challenges vs tutorials and quizzes

Challenges test what you can build under constraints. For guided teaching, use our Python tutorials. For quick checks, try quizzes or copy snippets from code samples.