You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named (5R)-3-methyl-9-(1-methyl-3-phenylthieno[2,3-c]pyrazole-5-carbonyl)-1-oxa-3,9-diazaspiro[4.5]decan-2-one by IUPAC nomenclature, provide its molecular formula.
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C21H22N4O3S
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