Any person under the age of twenty-one (21) years who has any alcoholic beverage in his possession on any street or highway or in any public place, or in any place open to the public is guilty of violating this Code. This section does not apply to possession by a person under the age of twenty-one (21) years making a delivery of an alcoholic beverage in pursuance of the order of his or her parent or in pursuance of his or her employment. (235 ILCS 5/6-16)