You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
N-ethyl-3-(1-methylpyrazol-4-yl)-N'-(2-thiophen-2-ylpropyl)pyrrolidine-1-carboximidamide is the IUPAC name of a molecule. Please give its molecular formula.
user
C18H27N5S
assistant