What does the extension Code Runner do?
It just runs the code. You still have to install the relevant compiler/interpreter for the language you're trying to run and set it up correctly in your settings.json so Code Runner can use the correct command.
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What does the extension Code Runner do?
As I have Python installed on my computer and also installed the Python extension by VSCode, then I had Code Runner uninstalled.
But I can't run Python scripts after that. It says "command 'code-runner.run' not found".
It just runs the code. You still have to install the relevant compiler/interpreter for the language you're trying to run and set it up correctly in your settings.json so Code Runner can use the correct command.
You can still run code from the terminal, if you don't want to have a separate extension