You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
4,8,10-triethyl-9-hydroxy-8,10,11-trimethyl-3-[(Z)-prop-1-enyl]-1,5-dioxa-9-azaspiro[5.5]undec-3-ene is the IUPAC name of a molecule. Please give its molecular formula.
user
C20H35NO3
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