Dear developers of PyPy: I found that there might be a little bug in `unicodeobject.py`. Our project relies on `sys.setdefautencoding('utf-8')` to handle string encoding things(we use Python2.7), which is not a good practice though, when we upgrade pypy to 7.1.0 and any version newer than it, our project stops working with tons of UnicodeEncodeError exceptions. There is already an issue 3329 <https://foss.heptapod.net/pypy/pypy/-/issues/3329#note_156942> described this problem, I left my comment <https://foss.heptapod.net/pypy/pypy/-/issues/3329#note_156942> below it which provided our solution to this problem. But I am not sure our solution is the correct way, and I tried to make a merge request but it then said that I don't have write permission, so I decided to write an email. I'm looking forward to hearing from you guys soon. Best regards, Kevin