With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: Islam has 1.8 billion followers.
text_B: The gunboat class HSY-55 is a class of naval vessel designed by the Hellenic Navy and built by Hellenic Shipyards -LRB- HSY -RRB- .. Hellenic Navy. Hellenic Navy. This class of ship uses the modular concept so that weapons and sensors can be changed as required .. These vessels are similar in appearance to Gunboats Class Osprey 55 .. Gunboats Class Osprey 55. Gunboats Class Osprey 55. The first pair was ordered on 20 February 1990 , but completion was delayed by the shipyard 's financial problems .. Pyrpolitis -LRB- P57 -RRB- was launched on 16 September 1992 , and Polemistis -LRB- P61 -RRB- on 21 June 1993 .. Each ship can carry 25 fully equipped troops .. Alternative guns and Harpoon SSM can be fitted as required .
not_related.