You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Translate the chemical IUPAC name 2-fluoro-1-[3-[3-[(E)-2-[3-(trifluoromethyl)phenyl]ethenyl]pyrazolo[3,4-b]pyridin-1-yl]azetidin-1-yl]prop-2-en-1-one into its molecular formula.
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C21H16F4N4O
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