The whole of Python foundations on one page, every line explained: syntax and control flow, functions, iterators and generators, data structures, strings and regex, object-oriented programming and packaging.
Python is easy to start and slow to consolidate. You learn comprehensions in one place, decorators in another, and the mutable default argument the hard way six months later. This sheet puts twenty-nine cards across seven topics side by side, each with the handful of lines that actually matter and a plain explanation of what every one of them does, so the language holds together as one picture instead of a pile of tutorials. Keep it open while you work, or save the image and pin it nearby.
It follows the Python foundations stage of the data scientist roadmap step for step, so each card on the sheet has a full article, a code-along and a Feynman explainer behind it when you want the reasoning rather than the reminder.
Happy Learning.
