You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
1-ethyl-4-[[(2S)-3-methylbutan-2-yl]amino]-N-[(2-methyl-1,3-thiazol-4-yl)methyl]pyrazolo[3,4-b]pyridine-5-carboxamide is the IUPAC name of a molecule. Please give its molecular formula.
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C19H26N6OS
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