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 N-(3-fluoro-4-methylphenyl)-2-(4-oxo-2-thiophen-2-ylpyrazolo[1,5-d][1,2,4]triazin-5-yl)acetamide into molecular formula.
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C18H14FN5O2S
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