No licensee shall fail to carry any license issued in accordance with the provisions of this Code upon his person at all times when engaged in the operation, conduct or carrying on of any business, or maintain the license where the business is operated at a fixed place in the establishment. Said license shall be exhibited at all times in some conspicuous place in the place of business. Every licensee shall produce its license for examination when applying for a renewal thereof or when requested to do so by a City police officer or by any person representing the City.