[Serhiy]
> I don't think this PR should be merged. It adds too much options.

[Daniel]
> Since opening this issue, I've encountered several additional 
> instances where indentation control would have been nice.
> I don't agree that jq is a sufficient substitute.

I'm inclined to agree with Serhiy.  While there are some handy command-line calls, they are secondary offshoots to the standard library and tend to be lightweight rather than full featured.  They serve various purposes from quick demos to support of development and testing.  In general, they aren't intended to be applications unto themselves: we don't document all command line tools in one place, we don't version number them, we don't maintain forums or web pages for them, we typically don't lock in their behaviors with a unit tests, we don't guarantee that they will be available across versions, and we periodically change their APIs (for example when switching from getopt to argparse).