It is unlawful for any person to transact, perform, engage in and carry on any business, trade, profession, calling or occupation in the city without first having procured a business license under this chapter to do so, paying the tax prescribed in this chapter and having complied with any and all applicable provisions of this chapter, including rules and regulations adopted by the appropriate authority to implement this chapter. The provisions of this section shall not be construed to require any person to obtain a license prior to doing business within the city if such requirement conflicts with applicable laws of the United States or of the state. Persons not so required to obtain a license prior to doing business within the city shall nevertheless be liable for the payment of the taxes imposed by the provisions of this chapter.
(`78 Code, § 5.02.030.)