You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule [4-[(1-ethylpyrazol-4-yl)methyl]piperazin-1-yl]-[1-methyl-3-(trifluoromethyl)thieno[2,3-c]pyrazol-5-yl]methanone into molecular formula.
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C18H21F3N6OS
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