as we totally accept two-element lists here as well as two-tuples. This is a little a symptom of lack of overloading (and lack of static typing therefore), but

as we totally accept two-element lists here as well as two-tuples. This is a little a symptom of lack of overloading (and lack of static typing therefore), but should be not hard to solve buy disjunctive hints like this one: [a]|(a,b) (and in case of Python, looks like Union[] would do?). The URL case is also pretty much the same and for example in Java you would have to write a different method signature for each such case and that would be natural. Again, disjunctive hints would solve this. Given that, I do not know what is the complaint really here. Perhaps that syntax is horrible, or it is hard to know what are the actual types in Python?