You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 4-[7-chloro-1-(2,6-difluorophenyl)-4-oxo-5H-pyrazolo[4,3-c]pyridin-3-yl]-N-morpholin-4-ylthiophene-2-carboxamide by IUPAC nomenclature, provide its molecular formula.
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C21H16ClF2N5O3S
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