hi

first post here :)
i have a recurring use pattern where i want to save to file everything i print to the screen. i have used the standard logging module and found it too cumbersome for my simple use case, and i find myself changing all my print()'s to custom myprint()'s. i am interested in suggesting several additions to the standard libraries, as i feel this use case is common enough, important enough, and currently painful enough to justify such changes, and that all four of the following suggestions could be useful in a complementary fashion.

1. allow the print() "file" argument to take a list of streams (currently it can take only a single stream). e.g:

with open('output.txt', 'w') as f:
   print('hello', file=[sys.stdout, f])

this seems like the quickest and least resistant path for the user. need to decide how multiple streams will work with the flush argument.

2. modify contextlib.redirect_stdout() to take an additional boolean argument which we can call tee/replicate/duplicate/clone etc. when True it will duplicate instead of just redirecting:

with open('output.txt', 'w') as f:
    with redirect_stdout(f, tee=True):  # will duplicate instead of redirecting
        print('hello')
3. allow the contextlib.redirect_stdout() "new_target" argument to take a list of streams, or allow specifying multiple arguments for multiple streams. e.g:

with open('output.txt', 'w') as f:
    with redirect_stdout(sys.stdout, f):  # or redirect_stdout([sys.stdout, f])
        print('hello')
4. add to the standard io library a new class which gives you the write interface of a single stream, but is a wrapper that will write to multiple streams:

with open('output.txt', 'w') as f:
   multi = io.OutputStreamCollection(sys.stdout, f)
   multi.write('hello\n')
   # or:  print('hello', file=multi)

eyal.