theorem instCoeFiatObjectPartMaterialEntity._proof_1
theorem instCoeFiatObjectPartMaterialEntity._proof_1: ∀ (v : d4qbfhxh.FiatObjectPart), d4qbfhxh.MaterialEntity.Is (Subtype.val v)
theorem instCoeFiatObjectPartMaterialEntity._proof_1
theorem instCoeFiatObjectPartMaterialEntity._proof_1: ∀ (v : d4qbfhxh.FiatObjectPart), d4qbfhxh.MaterialEntity.Is (Subtype.val v)