DEFINITION ex3_2_ind()
TYPE =
       A0:Set
         .A1:Set
           .P0:A0A1Prop
             .P1:A0A1Prop
               .P2:A0A1Prop
                 .P:Prop.(a:A0.a1:A1.(P0 a a1)(P1 a a1)(P2 a a1)P)(ex3_2 A0 A1 P0 P1 P2)P
BODY =
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