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 2,6-difluoro-N-[5-[1-(2-methyltetrazol-5-yl)-4-propan-2-yl-3,6-dihydro-2H-pyridin-5-yl]pyrazin-2-yl]benzamide into molecular formula.
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C21H22F2N8O
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