You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(2R)-5-chloro-N-[[2-(pyrrolidin-1-ylmethyl)phenyl]methyl]-2,3-dihydro-1-benzofuran-2-carboxamide The above is the IUPAC name of a molecule. Write its molecular formula.
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C21H23ClN2O2
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