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The Air Force is reportedly considering purchasing several squadrons of Sukhoi Su - 27 interceptors , considered the world ' s premier dogfighters .
 ( transfer ownership: purchasing,  interceptors: artifact, Air Force: buyer) 
Locate the role in the text that participated in the event based on the event type and return it in the event list. 
 Option: Event type: declare bankruptcy, transfer ownership, transfer money, marry, transport, die, phone write, arrest jail, convict, sentence, sue, end organization, start organization, end position, start position, meet, elect, attack, injure, born, fine, release parole, charge indict, extradite, trial hearing, demonstrate, divorce, nominate, appeal, pardon, execute, acquit, merge organization, Arguments type: beneficiary, prosecutor, plaintiff, seller, victim, buyer, agent, destination, artifact, organization, recipient, person, place, origin, target, giver, adjudicator, attacker, vehicle, defendant, entity, instrument. 
Text: {0} 
Answer:
 ( transfer ownership: purchasing,  interceptors: artifact, Air Force: buyer) 