> Any ideas? Sorry but I don't have one. My implementation is motivated from the six implementation https://bitbucket.org/gutworth/six/src/ca4580a5a648fc75abc568907e81abc80b05d58c/six.py?fileviewer=file-view-default#six.py-680 except they are defining a new function exec_() to prevent adding an extra frame AFAIK :)