Note that these results rely on a technical definition of set that is rather abstract mathematically, in a way programers may find amusing. It defines a set as

Note that these results rely on a technical definition of set that is rather abstract mathematically, in a way programers may find amusing. It defines a set as a potentially infinite list with potential duplicates, from which we can observe that some lists cannot be deduplicated in finite time, making certain operations that are easy on computer science sets not always possible on computer science lists. For example, is A a subset of B={0}, if all you know about A is that it is a Java iteratable that returns 0 for the first 10^3000 elements you examine?