You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
[3-[2-chloro-6-methyl-4-(4-methyl-6-oxo-4,5-dihydro-1H-pyridazin-3-yl)phenoxy]-2,2-difluoropropyl] benzoate is the IUPAC name of a molecule. Please give its molecular formula.
user
C22H21ClF2N2O4
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