You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 2-(4,6-dimethylpyrazolo[1,5-a]pyrazin-2-yl)-7-(1,2,3,6-tetrahydropyridin-4-yl)-1,9a-dihydropyrido[1,2-a][1,3]azaphosphinin-4-one into its molecular formula.
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C21H22N5OP
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