def find(order_id, id)
      _, _, root = @client.get("/orders/#{order_id}/line_items/#{id}")

      LineItem.new(root[:data])
    end
def find(order_id, id)
      _, _, root = @client.get("/orders/#{order_id}/line_items/#{id}")

      LineItem.new(root[:data])
    end
Retrieve a single line item

 get '/orders/{order_id}/line_items/{id}'

 Returns a single line item of an order, according to the unique line item ID provided

 @param order_id [Integer] Unique identifier of a Order
 @param id [Integer] Unique identifier of a LineItem
 @return [LineItem] Searched resource object.