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 3-[(3R,8aR)-6-ethyl-7,7-difluoro-5-oxo-1,2,3,6,8,8a-hexahydroindolizin-3-yl]-5-fluorobenzonitrile into molecular formula.
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C17H17F3N2O
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