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I am a Chinese citizen and I will be travelling from Copenhagen to Beijing. However I have a layover in Helsinki and recently I have been rejected a student visa in Sweden (I am allowed to travel from Copenhagen). I got a letter from the Swedish Migration Office that I have 4 weeks to leave the country, which expires on the 1st of June. The layover is no more than 4 hours and I do not plan to leave the airport. Do I still need the transit visa in Finland?