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For example , the apartments on the northern lots of each street were set back to allow for a front-yard , and those on the southern side were to be built adjacent to the street to allow for a backyard , so each building would get the maximum privacy and use of natural sunlight ( without much obstructions ) while providing the necessary space for the planting of a garden , greenery and/or trees for each house ( an essential part of Iranian and Persian architecture ) .
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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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