You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 5-methyl-6-phenyl-N-([1,2,4]triazolo[4,3-a]pyridin-3-ylmethyl)thieno[2,3-d]pyrimidin-4-amine into its molecular formula.
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C20H16N6S
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