Python is a dynamically typed language so when you say you've never used generics, that makes sense -- the concept does not apply to dynamically typed languages. But I bet you frequently use lists and dictionaries, and perhaps occasionally use higher-order functions like map, filter, and reduce. All of those would be generics in a typical statically typed language, because with static typing you don't just have "a list" but "a list of ints" or "a list of strings".

Go has built-in generic arrays, slices, and dictionaries, but nothing else, and you can't define your own functions that work on those without specifying the type. So say you write a function that shuffles the elements of an array, like Python's random.shuffle(list). You can't make your function work for all kinds of arrays. You have to have a different function to shuffle arrays of strings, arrays of ints, arrays of FooBarClass, etc. even though the shuffling logic doesn't give a damn about what sort of thing is in the array.

I have a suspicion that this occasionally leads developers to write code inline that they previously would've extracted into a utility function. See the answers here:

https://stackoverflow.com/questions/12264789/shuffle-array-i...