With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: The Caspian Sea is bounded by the Russian Federation to the northwest.
text_B: 70 mm Grandeur film , also called Fox Grandeur or Grandeur 70 , is a 70mm widescreen film format developed by the Fox Film Corporation and used commercially on a small scale in 1929 -- 31 .. 70mm. 70 mm film. widescreen. widescreen. Fox Film Corporation. 20th Century Fox. It was a forerunner of the Todd-AO 70mm system which was introduced in 1955 and is still in limited use -LRB- albeit with significant modifications -RRB- today .. 70mm. 70 mm film. Todd-AO. Todd-AO
not_related.