16832
Re-equipped with P-51 Mustangs , with a mission for escorting B-17 Flying Fortress and B-24 Liberator heavy bombers during its first five weeks of operations , and afterwards flew many escort missions to cover the operations of medium and heavy bombers that struck strategic objectives , interdicted the enemy 's communications , or supported operations on the ground .
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Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
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