You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named 3-ethyl-6-[(1-ethylcyclopentyl)methyl]-1-methyl-4H-imidazo[4,5-c]pyrazole-5-thione by IUPAC nomenclature, provide its molecular formula.
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C15H24N4S
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