Proofgold Proof

pf
Let x0 of type ι be given. Let x1 of type ι → ι → ι be given. Assume H0: Group (pack_b x0 x1). Apply H0 with explicit_Group x0 x1. Assume H1: struct_b (pack_b x0 x1). Assume H2: unpack_b_o (pack_b x0 x1) explicit_Group. Apply Group_unpack_eq with x0, x1, λ x2 x3 : ο . x2. The subproof is completed by applying H2. ■