During this COVID-19 lockdown, students are doing online programming from home. Can students use CodeRunner as a practice platform for Python 3. No testing/quiz at this stage, but just as an IDE-practise on tasks given, with no marks.
CodeRunner is designed as a quiz question type and is not intended as an on-line IDE. It is assumed that students develop and test their code in an IDE and then copy it into CodeRunner for submission and grading. If what you want is an on-line IDE there are lots of good options out there, such as repl.it.
However, if for some reason you wish students to develop their code directly on the Moodle server, you can provide a generic Python3 question, into which students can paste any code at all, click Check and see the result. The question should be configured with 0 marks and 0 penalties. This is a poor substitute for a real IDE but is much better than nothing.
I've created a quiz to demonstrate such a question here on this site. The question runs a given python program and displays the out in lieu of a result table. All submissions are deemed "correct". The student can even plot a graph with matplotlib and see the graph displayed. It might be useful, but please realise it's just a proof of concept. You'll probably need to modify it to suit your needs.