I recently stumbled on a Twitter thread by John Wiseman where GPT-3 quite impressively wrote and debugged a fibonacci function in a Python REPL. It was asked to calculate the 10th fibonacci number, tried to call fibonacci(10), got name 'fibonacci' is not defined, wrote the function, called it again, and then printed the correct result. It then went on further to try and calculate the 100th fibonacci number, which with the help of a timeout error it was able to optimize from the recursive form to the iterative form and calculate. Cool stuff!