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Hydrogen was liquefied for the first time by James Dewar in 1898 by using regenerative cooling and his invention , the vacuum flask .
 person: James Dewar
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: media, plant, vehicle, astronomical object, time, disease, animal, location, person, organization, mythical figure, food, biology, geographical phenomenon, instrument, event 
Text: {0} 
 Entities: James Dewar 
Answer:
 person: James Dewar