Comment by chubot

EDIT: I should also add that the length of PYTHONPATH as constructed by many package managers is a huge problem. You're doing O(m*n) stat()s -- random disk access -- which is the slowest thing your computer can do.

m is the number of libraries you're importing, and n is the length of the PYTHONPATH.

So it gets really bad, and it's not just one person's "fault". It's a collusion between the Python interpreter's import logic and how package managers use it.