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-[8-(2-chloro-5-fluorophenyl)-3-(hydroxymethyl)-6-oxo-7,8-dihydro-5H-imidazo[1,5-a]pyrazin-1-yl]-3-fluoro-5-(trifluoromethyl)benzamide into molecular formula.
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C21H14ClF5N4O3
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