proposition: Lemma _paco_convert3: forall T0 T1 T2 (paco3: forall (y0: @T0) (y1: @T1 y0) (y2: @T2 y0 y1) , Prop) y0 y1 y2 (CONVERT: forall (x0: @T0) (x1: @T1 x0) (x2: @T2 x0 x1) (EQ: _paco_id (@exist3T T0 T1 T2 x0 x1 x2 = @exist3T T0 T1 T2 y0 y1 y2)) , @paco3 x0 x1 x2), @paco3 y0 y1 y2.
proof: Proof. intros. apply CONVERT; reflexivity. Qed.