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-[[3,5-difluoro-4-(3,4,5-trifluorophenyl)phenoxy]methyl]-5-propyl-3,4-dihydro-2H-pyran into molecular formula.
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C21H19F5O2
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