[{"from": "human", "value": "Write weight-averaged molecular weight of given SMILES at room temperature and atmospheric pressure. ->  CC1=CC2=C(C(C3=NSN=C3C4=C5N(CCCCCCCCCCCC)C6=C4SC(C7=CC8=C(C(C=CC(C)=C9)=C9C8(CCCCCCCC)CCCCCCCC)C=C7)=C6)=C5N2CCCCCCCCCCCC)S1\n"}, {"from": "gpt", "value": " 20\n"}]