You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
N-[2-[(2-chloro-6-fluorophenyl)methylsulfanyl]ethyl]-2-(5-chloro-2-methyl-N-methylsulfonylanilino)acetamide is the IUPAC name of a molecule. Please give its molecular formula.
user
C19H21Cl2FN2O3S2
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