You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule 1-(1-cyclopropylpiperidin-4-yl)-2-methyl-3-(2-methyl-2-thiophen-2-ylpropyl)guanidine;hydroiodide into molecular formula.
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C18H31IN4S
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