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 (5S,9R)-2-(3,5-difluorophenyl)-7,7-difluoro-9-(2-oxo-2-pyridin-2-ylethyl)-2-azaspiro[4.5]decan-1-one into molecular formula.
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C22H20F4N2O2
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