You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule 5-cyclopropyl-2-[[(2,6-difluorophenyl)methyl-ethylamino]methyl]-4-phenyl-1,2,4-triazole-3-thione into molecular formula.
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C21H22F2N4S
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