DOC: ImportError: No module named pandas
Looks like #11604 is our most visited page on GitHub after the home (it's got half of the visits of the home, see "Popular content" in https://github.com/pandas-dev/pandas/graphs/traffic).

Someone recommended `sudo pip3 install pandas`, and I guess a person having that error will google it, read that issue and end up running that, which is not great.

I think we should have somewhere on the documentation information about that error, and give better information about the issue. And recommend using conda, discouraging pip, and creating an environment.

