With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: John II of Portugal's birthday was March 3rd, 1455.
text_B: Colombia will compete at the 2014 Summer Youth Olympics , in Nanjing , China from 16 August to 28 August 2014 .. Nanjing. Nanjing. Colombia. Colombia. 2014 Summer Youth Olympics. 2014 Summer Youth Olympics. China. China
not_related.