How to Temporarily Redirect stdout and stderr in Python Methods?

Redirecting stdout and stderr Temporarily

Is it possible to redirect stdout and stderr temporarily, specifically for the duration of a method in Python?

The Pitfall with Existing Solutions:

CurrentUserSolutions, unfortunately, don't genuinely redirect the streams; instead, they simply replace them entirely. However, this approach fails if a method possesses a local copy of either stream (for instance, due to its use as a parameter).

Context Manager-Based Solution:

Encapsulating the redirection logic within a context manager addresses this issue. Here's an example:

<code class="python">import os
import sys

class RedirectStdStreams:
    def __init__(self, stdout=None, stderr=None):
        self._stdout = stdout or sys.stdout
        self._stderr = stderr or sys.stderr

    def __enter__(self):
        self.old_stdout, self.old_stderr = sys.stdout, sys.stderr
        self.old_stdout.flush(); self.old_stderr.flush()
        sys.stdout, sys.stderr = self._stdout, self._stderr

    def __exit__(self, exc_type, exc_value, traceback):
        self._stdout.flush(); self._stderr.flush()
        sys.stdout = self.old_stdout
        sys.stderr = self.old_stderr

if __name__ == '__main__':

    devnull = open(os.devnull, 'w')
    print('Fubar')

    with RedirectStdStreams(stdout=devnull, stderr=devnull):
        print("You'll never see me")

    print("I'm back!")</code>

When used as shown in the example, this context manager temporarily redirects stdout and stderr to /dev/null, ensuring that any output from the "You'll never see me" line is effectively hidden while the redirect is active.

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