partial void DeleteDistrict(District instance);
 partial void UpdateDistrict(District instance);
		private void detach_Districts(District entity)
		{
			this.SendPropertyChanging();
			entity.Region = null;
		}
 partial void InsertDistrict(District instance);
		private void attach_Districts(District entity)
		{
			this.SendPropertyChanging();
			entity.Region = this;
		}