You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
3-methyl-2-methylsulfanyl-6-[(E)-2-pyridin-3-ylethenyl]-5-[4-(trifluoromethyl)phenyl]pyrimidin-4-one The above is the IUPAC name of a molecule. Write its molecular formula.
user
C20H16F3N3OS
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