With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: Heartbreak Ridge was filmed only in black and white.
text_B: The Tasmanian smelt , Retropinna tasmanica , is a small , pelagic freshwater smelt found in lowland streams of Tasmania , Australia .. Retropinna. Retropinna. pelagic. pelagic. freshwater. freshwater. smelt. smelt ( fish ). Tasmania. Tasmania. Australia. Australia
not_related.