You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 1-[2-(4-methyl-2,3,3a,4,6,6a-hexahydro-1H-pyrrolo[3,4-c]pyrrol-5-yl)acetyl]imidazolidin-2-one by IUPAC nomenclature, provide its molecular formula.
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C12H20N4O2
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