You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
methyl 2-cyclopentyl-2-(5,7-dimethyl-[1,2,4]triazolo[4,3-c]pyrimidin-3-yl)acetate is the IUPAC name of a molecule. Please give its molecular formula.
user
C15H20N4O2
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