You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Translate the chemical IUPAC name methyl 4-[(1S)-1-(2-fluorophenyl)-1,3,4,9-tetrahydropyrido[3,4-b]indol-2-yl]-4-oxobutanoate into its molecular formula.
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C22H21FN2O3
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