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 3-[[6-(3-carbamimidoylphenoxy)-3,5-difluoro-4-methylpyridin-2-yl]-methylamino]benzenecarboximidamide into molecular formula.
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C21H20F2N6O
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