[{"from": "human", "value": "Use the given information to create a molecule that fulfills the desired purpose. The molecule is a 4-carboxymethylenebut-2-en-4-olide."}, {"from": "gpt", "value": "[C][=C][C][=Branch1][C][=O][O][/C][\\-Ring1][=Branch1][=C][\\C][=Branch1][C][=O][O]"}]