You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named (3-fluoro-4-methylphenyl)-[(7R)-7-pyridin-3-yloxy-5-thia-2-azaspiro[3.4]octan-2-yl]methanone is given. What is its corresponding molecular formula?
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C19H19FN2O2S
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