Closed `sys.stdout` causes an endless stream of tracebacks in the repl

Bug report

Bug description:

Steps to reproduce:

Run Python 3.14.7 and enter the following:

import sys
f = open("file.txt", "w")
sys.stdout = f
f.close()

After the file is closed, the REPL attempts to display the next prompt.

Actual behavior:

The REPL repeatedly raises:

ValueError: I/O operation on closed file

This results in a very large stream of repeated tracebacks instead of returning to a usable prompt.
The traceback points to _pyrepl and eventually to:

_colorize.py", line 313, in can_colorize
    return os.isatty(file.fileno())
ValueError: I/O operation on closed file

Expected behavior:

The REPL should handle a closed sys.stdout gracefully instead of repeatedly emitting tracebacks.

Environment:

Python: 3.14.7
OS: Fedora Linux 44 (Workstation Edition) x86_64

CPython versions tested on:

3.14

Operating systems tested on:

Linux

Linked PRs

• gh-157590

Beginne mit dem _pyrepl-Traceback und dem can_colorize-Einstiegspunkt in _colorize.py ungefähr bei Zeile 313, und reproduziere dann den Fall mit geschlossenem sys.stdout in der Python 3.14 REPL. Erledigt ist die Aufgabe, wenn ein geschlossenes stdout keinen endlosen Strom von Tracebacks mehr erzeugt und die REPL den nächsten Prompt ordnungsgemäß verarbeitet.