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925 challenges 556 easy 323 medium 46 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 medium

Base64 Encode/Decode

Implement two functions to encode and decode Base64 strings using the standard alphabet and padding.

base64 encoding string

Data Formats & Parsing easy

Protocol definition

Parse a simple wire protocol string into a structured dictionary.

parsing protocol strings

Data Formats & Parsing easy

Config Parser Reader

Parse a simple INI-style configuration text into a nested dictionary.

parsing strings config

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

Parse email header

Write a function that parses a raw email header string and returns sender, recipient, and subject.

parsing strings email

Data Formats & Parsing easy

Update Row by ID

Given a list of CSV rows and target ID, replace the first matching row's value.

csv parsing list

Data Formats & Parsing easy

Parse CSV Row

Implement a robust function that parses a single CSV line into a list of fields, handling double quotes and escaped quotes.

csv parsing strings

Data Formats & Parsing easy

Parse Apache log line

Write a function that parses a single Apache access log line into a dictionary with IP, timestamp, request, status, and size.

parsing strings regex

Data Formats & Parsing easy

Parse table rows

Implement a function that converts a simple text table into a list of dictionaries.

parsing strings csv

Showing 1–12 of 12 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.