2660
The latter two have undergone comprehensive refits , including the insertion of a new hull section with an Air-independent propulsion system equipped with Stirling engine s. They have been recommissioned as the new Södermanland class .
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Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: location, person, organization 
Text: {0} 
Answer:
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