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In tapping into the world's email telephone and fax traffic and data bases the NSA relies on a network of spy satellites overseen by the  National Reconnaissance Office  based in  Chantilly  Virginia .
 city of headquarters: National Reconnaissance Office, Chantilly
Given a phrase that describes the relationship between two words, extract the words and the lexical relationship between them. The output format should be "relation1: word1, word2; relation2: word3, word4". 
Option: cities of residence, top members employees, members, alternate names, origin, state or provinces of residence, title of person, spouse, city of headquarters, NA, founded by, state or province of headquarters, employee of, countries of residence, country of birth, founded, subsidiaries, country of headquarters 
Text: {0} 
Answer:
 city of headquarters: National Reconnaissance Office, Chantilly