Session08

I would rather have the context manager throw an error if an improper file name is provided at the beginning.  Also, now that I see this code, I think that `something_filelike` is mis-named.  You are really expecting someone to pass a file *name*, not a file-like object.  I don't think this fits the specifics of the assignment as well.  Either fix it, or argue your case (I'm open to being persuaded, if you care to try).