You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named 6-[(2-ethyl-1,2,4-triazol-3-yl)methoxy]-3-(2-fluorophenyl)-7-(1,1,1-trideuterio-2-methylpropan-2-yl)-[1,2,4]triazolo[4,3-b]pyridazine by IUPAC nomenclature, provide its molecular formula.
user
C20H22FN7O
assistant