How to redirect 'print' output to a file?

Dude, where's my output?

To deal with more specific scenarios or to integrate logging, one has to roll their sleeves and dig deeper:

For scripts in one-time gigs or temporary redirection

Use this neat trick to redirect on-the-fly without altering the global sys.stdout (talk about being considerate!):

with open('output.txt', 'a') as f:
    print('I\'m just temporarily visiting!', file=f)
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This works wonders for one-off operations or within scoped sections of your code.

I got 99 problems and logging ain't one

Get cozy with Python’s logging module:

import logging

logging.basicConfig(filename='output.log', level=logging.INFO)
logger = logging.getLogger()

logger.info('This message will self-destruct in 5...4...3...(in output.log)')
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This guy here offers things like log levels and formatting, which are perfect for larger applications.

Path handling: Fast & Furious

Treat file paths with utmost regard:

import os

filename = os.path.join('my_directory', 'output.txt')
dirname = os.path.dirname(filename)

if not os.path.exists(dirname):
    os.makedirs(dirname)

with open(filename, 'w') as f:
    print('Home, sweet home!', file=f)
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This confirms that the path exists before the file moves in, helping to avoid awkward first-date-of-your-file-with-the-filesystem type of scenarios.

Avoiding common slip-ups

While redirecting output to a file, make sure you don't trip over these steps:

• When using print with file argument, keep in mind that you should be using Python 3.x, as Python 2.x users can't join the party.
• Always remember to close your file or use the with statement to prevent it from catching a cold (data loss or file corruption).
• Don't be that person who forgets to import modules (sys and os), right upfront.
• Be cautious when using 'w' mode. It overwrites existing files as if it had a grudge on them. Use 'a' mode to append and keep the peace.

When binaries got you jumbled

If you deal with binary data, remember not to use the print method:

with open('output.bin', 'wb') as f:
    f.write(b'Hello, darkness, my old friend...')
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This friend right here takes good care of binary data.

Let the shell take the wheel

Sometimes it's easier to let the command line do the heavy lifting:

python my_script.py > output.txt
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This shell command redirects all the print output into the output.txt. This could be a lifesaver for handling output in command-line scripts.