With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: Purple Haze is only a book.
text_B: RUMT may refer to  :. Hendrika van Rumt -LRB- 1897 -- 1985 -RRB- , Dutch gymnast. Hendrika van Rumt. Hendrika van Rumt. TRNA -LRB- uracil-5 - -RRB- - methyltransferase , an enzyme
not_related.