Whenever in this code, or in any city ordinance, a license or permit is required for the maintenance, operation or conduct of any business or establishment, or for doing business or engaging in any activity or occupation, any person, firm or corporation shall be subject to the requirement if, by himself or itself, or through an agent, employee or partner, he or it is held forth as being engaged in the business, activity or occupation, or if he or it solicits patronage therefor, actively or passively; or if he or it performs or attempts to perform any part of such business, activity or occupation in the city. (Prior code § 7-1-2)