You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name (2S,3S,8R)-N-(4-fluorophenyl)-1'-methyl-2'-oxospiro[1,2,5,6,7,8-hexahydropyrrolizine-3,3'-indole]-2-carboxamide into its molecular formula.
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C22H22FN3O2
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