You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
3-(4-fluorophenyl)-N'-[2-(1H-indol-3-yl)acetyl]-2-sulfanylidene-1H-imidazole-4-carbohydrazide The above is the IUPAC name of a molecule. Write its molecular formula.
user
C20H16FN5O2S
assistant