Mark Dickinson added the comment:
Thanks for the report. This is a long-standing and known behaviour. It's been
discussed a good few times before, and (quite apart from potential problems
with backwards compatibility) no-one has yet come up with convincing
alternative behaviours.
See
https
New submission from Ali Ramezani :
In CLI (Command Line Interpreter):
A tuple has a list component then try to += that component. Since tuple doesn't
allow assignment then it raises error but actually does that.
If you try actual equivalence (A=A+B) it does not.
Python 3.9.1 (tags/v3.9.1:1e5d
