A2 result

 In the regex_match part, I didn't get any marks, everything is error~ . Before I submitted the file, my code passed all the examples which are posted on Piazza, and we went to the Help Center, TA said if we tried all the examples and the results are the same as those on Piazza, we are good. And I think the problem is that I was looking 'r' as a RegexTreeNode but not a RegexTree, hence we got all errors for the unit test. (After running the unit test of a2, the error shows RegexTree has no attribute symbol), I think a remark must be request to get a mark we deserve