You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named ethyl (6aS)-5-(4-ethoxyphenyl)-4,6-dioxo-2,6a-dihydro-1H-pyrrolo[3,4-c]pyrazole-3-carboxylate is given. What is its corresponding molecular formula?
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C16H17N3O5
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