You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name N-[6-(difluoromethyl)pyridazin-4-yl]-11-ethyl-3-methyl-1,5,8,12-tetrazatricyclo[7.3.0.02,6]dodeca-2(6),7,9,11-tetraene-5-carboxamide;(1-fluoro-2-methylpropyl)phosphane into its molecular formula.
user
C21H27F3N7OP
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