You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule 5-[6-[(1S,5S)-6-methyl-3,6-diazabicyclo[3.2.0]heptan-3-yl]pyridazin-3-yl]-1H-indole into molecular formula.
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C18H19N5
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