You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
methyl 6-methyl-4-oxo-2,3,3a,5-tetrahydro-1H-triazolo[1,5-a]pyrazine-3-carboxylate is the IUPAC name of a molecule. Please give its molecular formula.
user
C8H12N4O3
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