[{"from": "human", "value": "Given SMILES, write its number-averaged molecular weight at room temperature and atmospheric pressure. ->  CC1=CC(C=C(OCC(CCCC)CC)C2=C3C(OCC(CCCC)CC)=CC4=C2SC(C5=C6C(C=C(C(C(CC)CCCC)=O)S6)=C(C)S5)=C4)=C3S1\n"}, {"from": "gpt", "value": " 4.86\n"}]