You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Can you give the molecular formula of the molecule (3R)-1'-propan-2-ylspiro[1H-indole-3,4'-5,7-dihydro-2H-pyrazolo[3,4-b]pyridine]-2,3',6'-trione ?
user
C16H16N4O3
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