Python · Beginner · 8 h

Python basics with real data

Types, lists, dictionaries, loops, functions and files, practised on a real CSV instead of toy examples.

Why employers care: Every Python screening test starts here. Analysts use it to automate what they used to do by hand.

Lessons, in order

How to install Python and run your first scriptInstall a current Python on Windows, macOS or Linux, set up VS Code, run a script from the terminal and fix the relative-path error every beginner hits.12 min
Python basics for beginners on a real datasetValues, lists, dictionaries, loops and functions, learned by answering real questions about 344 Palmer Penguins with nothing but the standard library.10 min
Python strings and numbers: f-strings, slicing, roundingClean messy rupee amounts and phone numbers with Python string methods, Decimal and f-strings, and learn the float, rounding and Unicode rules that trip up beginners.11 min
Python lists and tuples: slicing, sorting, comprehensionsBuild sorted leaderboards from real penguin data, write clean list comprehensions, and avoid the aliasing, copying and in-place traps that interviewers love.13 min
Python dictionaries and sets with real examplesUse dictionaries and sets to compare two years of real customer data, count products with Counter, merge settings and read nested JSON safely.14 min
Python if, for and while loops explainedTruthiness, the Python for loop with enumerate and zip, while loops, for...else, match/case and the walrus operator, built into a working command-line expense tracker.13 min