[issue32905] IDLE pyparse: fix initialization and remove unused code

[Terry J. Reedy]

New submission from Terry J. Reedy <tjreedy at udel.edu>:

Spinoff from #32880.
msg312394: dump duplicates print, except that sys.__stdout__ may be None.
msg312395: lastopenbracketpos is now always initialized in _study2, as was stmt_bracketing.  get_last_open_bracket_pos is never called.

Test are adjusted for removals.

----------
stage: patch review -> test needed

_______________________________________
Python tracker <report at bugs.python.org>
<https://bugs.python.org/issue32905>
_______________________________________