*** Formula: [(0, 1, 2), (3, 4, 5), (6, 7, 8)]
*** Item DType: (i8, i8, i8)
"custom (i8, i8, i8) :: [0,1,2]"
"custom (i8, i8, i8) :: [3,4,5]"
"custom (i8, i8, i8) :: [6,7,8]"

*** Formula: [("A", "B", "C"), ("D", "E", "F"), ("G", "H", "I")]
*** Item DType: (s, s, s)
"custom (s, s, s) :: [\"A\",\"B\",\"C\"]"
"custom (s, s, s) :: [\"D\",\"E\",\"F\"]"
"custom (s, s, s) :: [\"G\",\"H\",\"I\"]"

*** Formula: [((1, 2), (3, 4), (5, 6)), ((7, 8), (9, 10), (11, 12))]
*** Item DType: ((i8, i8), (i8, i8), (i8, i8))
"custom ((i8, i8), (i8, i8), (i8, i8)) :: [[1,2],[3,4],[5,6]]"
"custom ((i8, i8), (i8, i8), (i8, i8)) :: [[7,8],[9,10],[11,12]]"

*** Formula: [(), (), ()]
*** Item DType: ()
"custom () :: []"
"custom () :: []"
"custom () :: []"

