I'm asking because I'm using Python little and only for short scripts, so I didn't bother investigating much. Still I've been bitten a couple of times by bugs introduced by moving code around and not noticing that a line was not indented correctly. That in Python and in Haml (http://haml.info/) If somebody knows about those tools I will appreciate and it will make my life easier. BTW, I'm fixing somebody's else Python scripts right now :-)
Regardless of whom or what is doing the indentation, people still prefer reading code which is indented, even in a language which relies on braces or parenthesis for flow. The indenting is not for the compiler's sake, it has no problem understanding this: http://www.ioccc.org/2014/maffiodo1/prog.c
Also people get very picky and personal when it comes to indentation in ways that a computer can't always choose. I prefer to almost always indent and format my code myself, rather than letting the editor choose. Python is the only language I actually let my editor auto-format, because of PEP-8.
> Is there any automatical indentation function in some editor for Python?
Pretty much any editor will have a feature for this, or allow you to install a popular plugin for it in less than a minute.
if cond:
line
pasted line # where does it go?
This is just brackets/braces in disguise, at which point you might as well follow convention and use {}.
This is obviously a very personal issue, but for me, the whitespace has less cognitive load. E.g.: in languages with brackets, people usually still indent the code for readability.
I've also found that when teaching people to program, consistency works well. I think this is one of the reasons Python is easy to pick up, just because Python code consistently looks like Python.