You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule methyl (1R,3S,3aR,6aS)-1-(3-fluorophenyl)-3-(hydroxymethyl)-4,6-dioxo-5-phenyl-1,2,3a,6a-tetrahydropyrrolo[3,4-c]pyrrole-3-carboxylate into molecular formula.
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C21H19FN2O5
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