You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 6-chloro-8-fluoro-7-(5-fluoro-1H-indazol-4-yl)-5-methoxy-4-piperazin-1-ylquinazoline into its molecular formula.
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C20H17ClF2N6O
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