You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
What is the molecular formula of the molecule identified by 1-[8-[[(3R)-oxolan-3-yl]methyl]-2,8-diazaspiro[4.5]decan-2-yl]-2-pyridin-3-ylethanone ?
user
C20H29N3O2
assistant