For the purposes of this article “club” also means any county medical association having an authorized delegate to the California Medical Association and composed entirely of doctors of medicine duly admitted, licensed and qualified to practice medicine and surgery within the State, which has a bona fide membership of more than 1,000 members and has been in existence for a period of more than 20 years and which owns, leases, operates or maintains a club room or rooms for its members, and has operated the club room or rooms for a period of not less than three years.