It isn't a joke, you need the Kolmogorov complexity of the code that implements the feature, which has nothing to do with the fact that you're using someone else's solution. You may not have to think about all the code needed to parse a CSV, but
someone did and that's a cost of the feature, whether you want to think about it or not.
Again, if someone else writes a 100,000 line function for you, and they wrap it in a "do_the_thing()" method, you calling it is still calling a 100,000 line function, the computer still has to run those lines and if something goes wrong, SOMEONE has to go digging in it. Ignoring the costs you don't pay is ridiculous.