Added set of set handling (thru concept ISA)

tests/non_reg/test_sheerka_non_reg.py

@@ -255,7 +255,7 @@ as:
         assert isinstance(res[0].value.body, list)
 
     def test_i_can_create_concept_with_bnf_definition(self):
-        sheerka = self.get_sheerka(False, False)
+        sheerka = self.get_sheerka(use_dict=False, skip_builtins_in_db=False)
         a = Concept("a")
         sheerka.add_in_cache(a)
         sheerka.concepts_definition_cache = {a: OrderedChoice("one", "two")}
@@ -317,10 +317,10 @@ as:
         Same test then before,
         but make sure that the BNF are correctly persisted and loaded
         """
-        sheerka = self.get_sheerka(False)
+        sheerka = self.get_sheerka(use_dict=False)
         concept_a = sheerka.evaluate_user_input("def concept a from bnf 'one' 'two'")[0].body.body
 
-        res = self.get_sheerka(False).evaluate_user_input("one two")
+        res = self.get_sheerka(use_dict=False).evaluate_user_input("one two")
         assert len(res) == 1
         assert res[0].status
         assert sheerka.isinstance(res[0].value, concept_a)
@@ -328,12 +328,12 @@ as:
         # add another bnf definition
         concept_b = sheerka.evaluate_user_input("def concept b from bnf a 'three'")[0].body.body
 
-        res = self.get_sheerka(False).evaluate_user_input("one two")  # previous one still works
+        res = self.get_sheerka(use_dict=False).evaluate_user_input("one two")  # previous one still works
         assert len(res) == 1
         assert res[0].status
         assert sheerka.isinstance(res[0].value, concept_a)
 
-        res = self.get_sheerka(False).evaluate_user_input("one two three")  # new one works
+        res = self.get_sheerka(use_dict=False).evaluate_user_input("one two three")  # new one works
         assert len(res) == 1
         assert res[0].status
         assert sheerka.isinstance(res[0].value, concept_b)