You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
1-(3-methylphenyl)-6-oxo-N-[(1S)-1-[(2S)-oxolan-2-yl]ethyl]-4,5-dihydropyridazine-3-carboxamide is the IUPAC name of a molecule. Please give its molecular formula.
user
C18H23N3O3
assistant