7. Gift tax officers. Every Income- tax Officer having jurisdiction or exercising powers as such under the Income- tax Act in respect of any person shall perform the functions of a Gift- tax Officer under this Act in respect of that person: 3[ Provided that the where two or more Income- tax Officers have jurisdiction or exercise powers under the income- tax Act in respect of any person, they shall have concurrent jurisdiction and shall perform their functions of a Gift- tax Officer under this Act in respect of such person in accordance with such general or special. orders in writing as the- Commissioner or the Inspecting Assistant Commissioner authorised by the Commissioner in this behalf, may make for the" purpose of facilitating the performance of such functions.] Explanation.- For the purposes of this section, the Income- tax Officer or Income- tax Officers having jurisdiction in relation to a person who has no income assessable to Income- tax under the Income- tax Act, shall be the Income- tax Officer or Income- tax Officers in respect of the area in which that person resides.] Power of Commissioner respecting specified areas, cases or persons.