I'm in the final section in the course, File I/O, I didn't close a file after I had opened it (just because I wanted to see what would happen) on Lesson 4. Ever since then, I get an error whenever I try to submit code for Lesson 5 on. The popup tells me:
"Oops, try again. Sorry, but I'm gonna need you to refresh the page! Don't worry your code is saved."
no matter what I submit as code (even if I'm not doing any I/O). I think I somehow messed up the system's way of doing I/O by not closing the file. I have refreshed the page and no changes occur. Is there anything I can do to fix this? Thank you.