With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: Princess Margaret was a heavy smoker.
text_B: Vasyugan is a river in the southern West Siberian Plain of Russia .. West Siberian Plain. West Siberian Plain. Russia. Russia. It is a tributary of the Ob River on the left side , and its course from its source in the Vasyugan Swamp is entirely within the Kargasok district of Tomsk Oblast .. tributary. tributary. Ob River. Ob River. Vasyugan Swamp. Vasyugan Swamp. Tomsk Oblast. Tomsk Oblast
not_related.