Customary residential accessory building for private use, such as pergola, greenhouse, hot house, hobby shop, or summer house, above-ground pool, patio, enclosed or covered patio, woodshed, quarters for domestic animals maintained as pets of the residents. This shall not include livestock of any kind including cattle, or other livestock or poultry, except as provided in Section 10.21.030. In no instance shall goats or pigs be maintained on any lot within the City limits;