You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 5-chloro-8-nitro-7-(trifluoromethyl)-1,4,4a,5-tetrahydroquinoxaline-2,3-dione by IUPAC nomenclature, provide its molecular formula.
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C9H5ClF3N3O4
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