You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule N-(6-chloro-4b-methyl-8a,9-dihydropyrido[3,4-b]indol-8-yl)-2-fluorocyclohexa-2,4-diene-1-carboxamide into molecular formula.
user
C19H17ClFN3O
assistant