[{"from": "human", "value": "Generate a molecule based on the given description. The molecule is a dicarboxylic acid dianion obtained by the deprotonation of both the carboxy groups of acetylenedicarboxylic acid. It is a C4-dicarboxylate and a dicarboxylic acid dianion. It is a conjugate base of an acetylenedicarboxylate(1-)."}, {"from": "gpt", "value": "[C][#Branch1][#Branch1][#C][C][=Branch1][C][=O][O-1][C][=Branch1][C][=O][O-1]"}]