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I am traveling from Toronto to Ahmedabad via Chicago and Doha and same way back. I am traveling from Toronto to Chicago in Air Canada and in Qatar from Chicago to Doha to Ahmedabad. Same way back. How will the baggage claim, customs and immigration work? While coming back, do I have to get my luggage at Chicago airport, undergo customs, and take all the baggage with me on the train, change terminals, and re-check my luggage at the Air Canada counter, or do I not have to worry about my luggage and it gets automatically transferred?