* In IDLE sys.stdout.isatty() returns True, but sys.stdout.fileno() raises an exception. Terminal width can't be determined and the default 80 is used.

* You always can pass explicit width to pprint. This may be needed even with default width 80. Now on wide a terminal wider 80 columns you have unused space than can cause unneeded wrapping. On a terminal narrower 80 columns the pprint() output is formatted incorrectly and is wrapped twice: by pprint() and by terminal.

* The output in doctests is not connected to a terminal.