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-[2-(cyclopropylmethoxy)ethyl]-3-[5-(2-imidazo[1,5-a]pyridin-6-ylethynyl)-4-methyl-1,3-thiazol-2-yl]urea into molecular formula.
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C20H21N5O2S
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