With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: The Twilight Saga stars an American actress.
text_B: Desert Runners is a 2013 documentary film directed by Jennifer Steinman that follows a group of non-professional runners that attempt to complete 4 Deserts , a series of ultramarathon races often considered the most difficult in the world .. documentary film. documentary film. 4 Deserts. 4 Deserts. ultramarathon. ultramarathon. Their journeys take them through some of the world 's most beautiful places while pushing the limits of their minds and bodies .. It provides a look into the mindset of endurance athletes , and the ways in which humans deal with both heartbreak and achievement .
not_related.