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819 challenges 506 easy 280 medium 33 hard

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Data Formats & Parsing medium

Extract JSON-like numbers

Parse a simplified JSON-like string without using the json module and sum all numbers found in it.

json parsing numbers

Data Formats & Parsing easy

Generate CSV row

Implement a function that converts a list of values into a single CSV row with correct quoting and escaping.

csv escaping strings

Data Formats & Parsing easy

Parse YAML-like dict

Parse a simple YAML-like text with indentation into a nested dictionary.

parsing yaml dictionary

Data Formats & Parsing medium

Flatten nested JSON

Write a function that flattens nested JSON objects into a flat dictionary with dot-separated keys, handling lists and empty objects.

json recursion dictionaries

Data Formats & Parsing medium

Unflatten JSON dict

Given a flat dictionary with keys like 'a.b.c', reconstruct the nested dictionary where each dotted segment becomes a nested level.

json dict parsing

Data Formats & Parsing easy

Encode Base64 String

Write a function that encodes a UTF-8 string into a base64 string without using the base64 module.

base64 encoding strings

Data Formats & Parsing medium

Serialize dict to TOML-like

Convert nested Python dicts into a simplified TOML-like string with sorted keys, type-aware formatting, and flat table sections.

dict toml serialization

Showing 7 challenges · Data Formats & Parsing

Data Formats & Parsing — Python coding challenges

What you will find here

This page lists data formats & parsing challenges — real Python problems you solve in the browser IDE with instant test feedback. Each challenge includes a clear brief, starter code, and automated checks.

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.