I built Python Playground, a Chrome extension that gives you a ready-to-use Python environment right in your browser - no installation needed.
It runs Python locally via Pyodide (WebAssembly) with most popular libraries included out of the box, plus a package manager to install additional modules from PyPI. The environment supports inline data visualization with Matplotlib and Plotly, file upload/download through a sandboxed filesystem, and the ability to save and reload snippets. Everything executes entirely on the client, so it works offline and nothing ever leaves your browser.
In addition to the extension, there’s also a web version you can try right away: https://python-playground.com
I’m planning to add debugging tools, synchronization between devices, and possibly more advanced features over time. I would be very interested to hear your feedback and what improvements you think would be most useful.