You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(2-ethylpiperidin-1-yl)-[6-(4-fluorophenyl)-3-methylimidazo[2,1-b][1,3]thiazol-2-yl]methanone is the IUPAC name of a molecule. Please give its molecular formula.
user
C20H22FN3OS
assistant