Get a set of random pages.
Pages are listed in a fixed sequence, only the starting point is random. This means that if, for example, "Main Page" is the first random page on your list, "List of fictional monkeys" will *always* be second, "List of people on stamps of Vanuatu" third, etc.
If the number of pages in the namespace is lower than $1limit, you will get fewer pages. You will not get the same page twice.