901 Provided that where charges for lodging are levied otherwise than on daily basis or person, then, for the purpose of determining the tax liability of any person under this section, the charges shall be computed as for a day and per person, based on the period of lodging for which charges are payable and the number of persons actually lodging or permitted to lodge according to the rule or custom of the hotel: Provided further that where any charges for lodging are paid by any person other than a citizen of India in any foreign exchange, then such person or where such charges are paid by any person or class of persons as the State Government may, by order, direct such as foreigners staying as guests in India of any Government or of any Corporation or Company owned or controlled by Government, or such other person as in the opinion of the State Government it is expedient in the public interest to exempt, then such person or per sons shall be exempt from the payment of the tax.