You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named (2-ethyl-5-methylpyrazol-3-yl)-[8-(2-pyridin-3-yloxyethyl)-5-oxa-2-azaspiro[3.4]octan-2-yl]methanone is given. What is its corresponding molecular formula?
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C20H26N4O3
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