13955
In the first season ( 1971 – 1972 ) , a number of unbilled children were also used on-camera with the show 's cast , as on " Sesame Street " , but this concept was quickly dropped .
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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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