DEFINITION csuba_getl_abst_rev()
TYPE =
       g:G
         .c1:C
           .d1:C
             .u:T
               .i:nat
                 .getl i c1 (CHead d1 (Bind Abst) u)
                   c2:C
                        .csuba g c2 c1
                          (or
                               ex2 C λd2:C.getl i c2 (CHead d2 (Bind Abst) u) λd2:C.csuba g d2 d1
                               ex2_2 C T λd2:C.λu2:T.getl i c2 (CHead d2 (Bind Void) u2) λd2:C.λ:T.csuba g d2 d1)
BODY =
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