> We can change every occurrence of this kind of print with stderr.write, but I
> think it's not that necessary since this is only a benchmark script, which is
> not supposed to be included to any other script, hence the side effect is OK.
> What do you think?

My worry is that people code by imitation, and will replicate this code.
I don't think that this is the best way to do it, and I think that
writing to sys.stderr, or explicitely flushing sys.stdout is better
style. So, to avoid propagation of this pattern in the codebase, I would
prefer not using it here.