You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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1-[(4-chlorophenyl)methyl]-3-[2-(2,3-dihydro-1,4-benzodioxin-6-yl)propan-2-yl]urea is the IUPAC name of a molecule. Please give its molecular formula.
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C19H21ClN2O3
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