You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Can you give the molecular formula of the molecule 9-[5-(4-chloro-1H-pyrrol-2-yl)-1,2,4-oxadiazol-3-yl]-6,6a,7,8,9,10-hexahydropyrido[2,1-c][1,4]benzothiazepin-12-one ?
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C19H17ClN4O2S
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