That's the point, there is no magic library that can do this for you. For example, let's say you're writing Python and have a list of receipt numbers. When you get a new receipt, you want to check if it's already in the list, so you do the pythonic thing: "if receipt_nr in receipts", assuming that the standard implementation of this operation in the library is efficient. The problem is, a set would be a lot more efficient here, but the standard library doesn't know you'll be checking if a number is in the list many times, so it cannot use the appropriate data structure.

So, in a way, the time and space complexity of each operation is part of the interface: maybe you don't really need to know how the internals are implemented, but at the very least you need to know the time and space complexity of the data structures you're using, and how to analyse the complexity of your code.