(define soln (SetLink (ListLink (ConceptNode "A") (ConceptNode "B"))))
(define test
(QueryLink
(VariableList
(TypedVariableLink (VariableNode "$var1") (TypeNode "ConceptNode"))
(TypedVariableLink (VariableNode "$var2") (TypeNode "ConceptNode"))
(TypedVariableLink (VariableNode "$var3") (TypeNode "ConceptNode"))
)
(AndLink
(ListLink
(VariableNode "$var1")
(VariableNode "$var2")
)
(AbsentLink
(ListLink
(VariableNode "$var3")
(ConceptNode "X")
)
)
)
(ListLink
(VariableNode "$var1")
(VariableNode "$var2")
)
)
)