Support a Clear Screen command in IDLE

[gryphonB-2]

Bug report

Bug description:

As we all know, there is no way to clear input/output from the Idle Shell.
Unlike in a terminal, which has always had this facility.
I am currently working through Learning Python, 5ed, co 2013, where he complains about the same thing.
I would guess that Idle is a decade older than that.
I would suggest that, after 20 years , Idle should be at least as capable as a terminal, and that after 20 years the lack of a 'clear' command constitutes a bug, not a feature request.
Cheers

CPython versions tested on:

3.12

Operating systems tested on:

Linux

[picnixz]

Even if it's decades later, we would still consider it a feature request first as per our feature policy. Sorry.

[picnixz]

Actually, this is a duplicate of #50393.

[terryjreedy]

@gryphonB-2 There has never been agreement on precisely what to do. Feel free to add a comment to the original issue. Prompted by this duplicate, I just added a comment on the separate solutions that I think would handle most use cases.

[terryjreedy]

For IDLE (see PEP-434), bug versus feature usually makes no difference w/r/to backports. The main difference is that what to do for bugs is usually clear: fix the behavior, or possible the doc. The main problem is how to do so. Features, like this one, are much more likely to get hung up on the details of what to do.