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 2-[2-amino-2-oxo-1-[3-(trifluoromethyl)-4,5,6,7-tetrahydroindazol-1-yl]ethyl]-4-ethyl-5-methylthiophene-3-carboxamide into molecular formula.
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C18H21F3N4O2S
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