theorem instCoeFiatObjectPartMaterialEntity._proof_1
theorem instCoeFiatObjectPartMaterialEntity._proof_1: ∀ (v : ta3nj1a4.FiatObjectPart), ta3nj1a4.MaterialEntity.Is (Subtype.val v)
theorem instCoeFiatObjectPartMaterialEntity._proof_1
theorem instCoeFiatObjectPartMaterialEntity._proof_1: ∀ (v : ta3nj1a4.FiatObjectPart), ta3nj1a4.MaterialEntity.Is (Subtype.val v)