My test code in Moodle is looking for a particular function name. In Thonny as long as the function call and funciton definition use the same name, you could name the function anything.
My test code has the function call, at it is looking for printPowersOfN (notice the capital F in oF). If you change the name of the function in your function definition to have a capital F, you should be good to go.
Thanks for asking in the Q&A!