Serhiy Storchaka added the comment: PySequence_Tuple() was changed to PySequence_List() in the changeset 4714aff4bf75 in 2004. Are there any measurements which show PySequence_List() faster than PySequence_Tuple() on modern Python? I don't see any references in 4714aff4bf75 description. ---------- nosy: +serhiy.storchaka _______________________________________ Python tracker <report@bugs.python.org> <http://bugs.python.org/issue16395> _______________________________________