You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule 2-[[7-(4-fluorophenyl)-8,8-dimethyl-1,7-diazaspiro[4.4]nonan-1-yl]methyl]-4-methyl-1,3-thiazole into molecular formula.
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C20H26FN3S
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