Usage ----- There are three commands `list`, `submit`, and `retrieve`. racket handin.rkt <command> ... list: Lists available assignments open for submission. racket handin.rkt list submit: Submits a file to the handin server for an assignment. racket handin.rkt submit <assignment> <filename> retrieve: Retrieves a file from the server for an assignment. racket handin.rkt retrieve <assignment> <filename> Dependencies ------------ Racket (only tested on 6.1) PL plugin installed.