Rick, 
 
Since this isn't a one-off item, but as you say ethnically common, it must have some cultural significance and not likely a bag to carry extra socks. What could/would be carried to produce that shape? First aid, natural roots & leaves for medicines, personal items, magic items? We need to dive deeper into their culture. 
 
Best, 
Ed
		 
		
		
		
		
		
		
		
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