You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 1-[2-(2-chloro-4-methoxyphenyl)ethyl]-3-[[6-(2-methoxyethoxy)pyridin-3-yl]methyl]-2-methylguanidine into its molecular formula.
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C20H27ClN4O3
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