You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
4-(difluoromethoxy)-1-methyl-2-[5-(1-methyl-5-propan-2-ylpyrrolidin-3-yl)oxyhexan-2-yl]pyrrolidine is the IUPAC name of a molecule. Please give its molecular formula.
user
C20H38F2N2O2
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