You can't see what character whitespace actually is
The very first time I used Python this exact thing happened to me. Transferred a largeish script from school computer (which used tabs) to my own IDE (which used spaces). It took me forever to even realize what was wrong. I still use Python from time to time, but I wouldn't use it for anything large that requires multiple people.
Half of the huge threads on stories are about things that only very vaguely (if at all) have anything to do with the topic. 2 people get into an argument about something really fucking stupid like hosts files (hi APK) on an article about Fukushima, etc.
To be honest that's half the reason I even read the comments anymore. It can be quite interesting to see exactly HOW those discussions get so far off track.
Unix is the worst operating system; except for all others. -- Berry Kercheval