[{"from": "human", "value": "Generate a molecule based on this description. Radiopaque medium usually in oil; used in bronchography."}, {"from": "gpt", "value": "[C][C][C][O][C][=Branch1][C][=O][C][N][C][=C][Branch1][N][C][=Branch1][C][=O][C][=Branch1][Ring2][=C][Ring1][#Branch1][I][I]"}]