You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
6-(4-cyclopropylpiperazin-1-yl)-2-(6-methylpyrazolo[1,5-a]pyrazin-2-yl)-3H-quinazolin-4-one is the IUPAC name of a molecule. Please give its molecular formula.
user
C22H23N7O
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