You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 3-chloro-4-[4-(2-oxa-8-azaspiro[4.5]decan-8-yl)furo[3,2-c]pyridin-7-yl]sulfanylpyridin-2-amine by IUPAC nomenclature, provide its molecular formula.
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C20H21ClN4O2S
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