You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-cyclobutyl-N-(6,7-dihydro-5H-pyrrolo[1,2-a]imidazol-3-ylsulfonyl)-1-methylpyrrole-3-carboxamide is the IUPAC name of a molecule. Please give its molecular formula.
user
C16H20N4O3S
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