With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: Sam Smith worked with Alicia Keys.
text_B: The Mark of Cain is a 1916 American silent drama film directed by Joe De Grasse and starring Lon Chaney .. Joe De Grasse. Joe De Grasse. Lon Chaney. Lon Chaney, Sr.. silent. silent film. drama film. drama film
not_related.