You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 8-(difluoromethoxy)-6-fluoro-1-(2-hydroxyethyl)-4-oxo-7-(4-pyrimidin-2-ylpiperazin-1-yl)quinoline-3-carboxylic acid into its molecular formula.
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C21H20F3N5O5
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