You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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ethyl (4R)-4-ethyl-6-[(2-fluorophenyl)sulfanylmethyl]-2-oxo-3,4-dihydro-1H-pyrimidine-5-carboxylate is the IUPAC name of a molecule. Please give its molecular formula.
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C16H19FN2O3S
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