With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: David Thewlis was born in 1983.
text_B: The Nantan meteorite is an iron meteorite that belongs to the IAB group and the MG -LRB- main group -RRB- subgroup .. iron meteorite. iron meteorite. IAB. IAB meteorite. , pieces of Nantan meteorite were on sale at  /  g.
not_related.