You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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4-[1-[8-tert-butyl-2-(4-fluorophenyl)-3-oxo-1,4-diazaspiro[4.5]dec-1-en-4-yl]propyl]benzaldehyde is the IUPAC name of a molecule. Please give its molecular formula.
user
C28H33FN2O2
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