Got it.
I now use the find() function to see if it returns a position greater then -1. If so, then the decision returns true, else it returns false.
if find ( '0101, 0104, 0105, 0106, 0107, 0108, 0109, 0110, 0111, 0114,
0115, 0120, 0122, 0130, 0202, 0203, 0205, 0206, 0207, 0208,
0209, 0213, 0214, 0220, 0221, 0222, 0223, 0224, 0225, 0226,
0227, 0228, 0229, 0230, 0231, 0232, 0233, 0234, 0235, 0236,
0237, 0241, 0242, 0243, 0244, 0245, 0246, 0248, 0249, 0250,
0301, 0302, 0303, 0304, 0305, 0307, 0308, 0309, 0313, 0314,
0320, 0321, 0322, 0350, 0360, 0400, 0401, 0402, 0403, 0404,
0405, 0410, 0411, 0415, 0416, 0419, 0420, 0421, 0422, 0425,
0426, 0427, 0429, 0432, 0436, 0437, 0438, 0440, 0441, 0443,
0445, 0447, 0448, 0450, 0481, 0482, 0483, 0484, 0485, 0487,
0488, 0489, 0490, 0491, 0492, 0493, 0494, 0495, 0499, 0501,
1256', $Instance/Attribute ) > -1
then true
else false