You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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N-[(5-methylpyrazin-2-yl)methyl]-7-propan-2-yl-1-oxa-2,7-diazaspiro[4.4]non-2-ene-3-carboxamide is the IUPAC name of a molecule. Please give its molecular formula.
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C16H23N5O2
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