On https://github.com/maths/moodle-qtype_stack/blob/master/doc/en/Authoring/Answer_tests.md
you can read about an answer test named "Sets":
Sets
This test deals with equality of sets. The algebraic equivalence functions give very minimal feedback. This test is designed to give much more detailed feedback on what is and is not included in the student's answer. Hence, this essentially tells the student what is missing. This is kind of feedback is tedious to generate without this test.
The test simplifies both sets, and does a comparison based on the simplified versions. The comparison relies on ev(..., simp, nouns)
to undertake the simplification. If you need stronger simplification
(e.g. trig) then you will need to add this to the arguments of the
function first.
But I can't find the entry "Sets" in my dropdown list in the prt.
Can anybody help me?
Regine