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 2-fluoro-N-[(2R)-3-methyl-1-[3-(1-methyltetrazol-5-yl)anilino]-1-oxobutan-2-yl]benzamide into molecular formula.
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C20H21FN6O2
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