You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-(2,3,3a,4,6,6a-hexahydro-1H-pyrrolo[3,4-c]pyrrol-5-yl)-4-methylpyridine-3-carboxamide The above is the IUPAC name of a molecule. Write its molecular formula.
user
C13H18N4O
assistant