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The Dark Knight is estimated to be on track to sell 26 million dollars in tickets this weekend bringing the  Warner Bros.  release up to an estimated 441.5 million dollars in business in the  United States  and Canada alone by the close of business Sunday night according to Media By Numbers .
 country of headquarters: Warner Bros., United States
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:
 country of headquarters: Warner Bros., United States