You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-[[3-[3-(trifluoromethyl)phenyl]imidazo[1,2-b]pyridazin-6-yl]amino]-7-azaspiro[3.5]nonan-6-ol The above is the IUPAC name of a molecule. Write its molecular formula.
user
C21H22F3N5O
assistant