You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 9-amino-N-[(1-methyl-2-thiophen-2-ylpiperidin-3-yl)methyl]bicyclo[3.3.1]nonane-3-carboxamide;dihydrochloride by IUPAC nomenclature, provide its molecular formula.
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C21H35Cl2N3OS
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