57017
Railway Workers Union since risen and stood back in 1999 until now has undertaken the following activities : SPKA in order to motivate employees who served in the pron liner such as track guards , guards the tunnel and depot-depot machinist in Java and Sumatra , on a working visit by way of dialogue .
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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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