With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: Perth is an Australian capitol city.
text_B: Blondie 's Blessed Event is a 1942 black and white comedy film , directed by Frank R. Strayer .. Frank R. Strayer. Frank R. Strayer. It is the eleventh of the Blondie films .
not_related.