You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Please write the molecular formula of the molecule 2-[2-(6,7-dihydro-4H-thieno[3,2-c]pyridin-5-yl)-2-phenylethyl]-1,1,3,3-tetramethylguanidine;hydroiodide .
user
C20H29IN4S
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