Add `reversed` function
Python's reversed returns a reverse iterator for looping over arrays. Docs: https://docs.python.org/3.8/library/functions.html#reversed
In JS we could create a function that returns the array, but with its elements in reverse order. See Wakefield's implementation: https://discourse.psychopy.org/t/how-to-store-and-save-correct-answers-with-a-set-of-digits-as-response-in-digit-span-task/22483/56?u=thomas_pronk