You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-[(2-chloro-6-fluorophenyl)methyl]-5-(1-methylsulfonylpiperidin-4-yl)-4-thiophen-2-yl-1,2,4-triazol-3-one is the IUPAC name of a molecule. Please give its molecular formula.
user
C19H20ClFN4O3S2
assistant