With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: Tanzania's principal port and leading commercial center is Dar es Salaam.
text_B: Gambit is a Nero Wolfe detective novel by Rex Stout , first published by the Viking Press in 1962 .. Rex Stout. Rex Stout. Nero Wolfe. Nero Wolfe. Viking Press. Viking Press. 1962 in literature. detective novel. detective novel
not_related.