How to print to stderr in Python?

Question

There are many ways to write stderr:

 # Note: this first one does not work in Python 3

 print >> sys.stderr, "spam"

sys.stderr.write("spam\n")

os.write(2, b"spam\n")

from __future__ import print_function

print("spam", file=sys.stderr)

That seems to contradict zen of Python #13 †, so what's the difference here and are there any advantages or disadvantages to one way or the other? Which way should be used?

† There should be one — and preferably only one — obvious way to do it.

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Answer 1

You can refer to this code:

from __future__ import print_function

import sys

def eprint(*args, **kwargs):

print(*args, file=sys.stderr, **kwargs)

This is much easier and flexible than the other methods. Here, the eprint function behaves the same as the print function:

Ex-

>>>print(“Hello”)

Hello

>>>eprint(“Hello”)

Hello

Answer 2

import sys

sys.stderr.write()

You can use the following video tutorials to clear all your doubts:-