You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 8-[(2E)-2-[(3-ethoxy-4-hydroxyphenyl)methylidene]hydrazinyl]-1,3-dimethyl-7-(2-methylprop-2-enyl)purine-2,6-dione into its molecular formula.
user
C20H24N6O4
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