You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
[1-(3-chloropyridin-2-yl)-5-(trifluoromethyl)pyrazol-4-yl]-[(2R)-2-methyl-4-(oxan-4-yl)piperazin-1-yl]methanone The above is the IUPAC name of a molecule. Write its molecular formula.
user
C20H23ClF3N5O2
assistant