353383
San Metal Open Air in Germany on August 8 , 2008 , Pellavarock in Finland on August 9 , 2008 , Hellfest in France on June 22 , 2010 and Bloodstock Open Air in England on August 15 , 2010 .
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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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