141166
They are , in the words of the composer , " a newly conceived set of preludes for the modern piano which takes its material from the seven colours of the rainbow , the seven pitches of church modes , and seven metrical units ranging from three to nine beats . "
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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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