code: def get_cfn_attribute(self, attribute_name):
          '''
          Implemented attributes:
          * DNSName
          * LoadBalancerName
  
          Not implemented:
          * CanonicalHostedZoneID
          * LoadBalancerFullName
          * SecurityGroups
  
          This method is similar to models.py:FakeLoadBalancer.get_cfn_attribute()
          '''
          from moto.cloudformation.exceptions import UnformattedGetAttTemplateException
          not_implemented_yet = [
              'CanonicalHostedZoneID',
              'LoadBalancerFullName',
              'SecurityGroups',
          ]
          if attribute_name == 'DNSName':
              return self.dns_name
          elif attribute_name == 'LoadBalancerName':
              return self.name
          elif attribute_name in not_implemented_yet:
              raise NotImplementedError('"Fn::GetAtt" : [ "{0}" , "%s" ]"' % attribute_name)
          else:
              raise UnformattedGetAttTemplateException(f get_cfn_attribute(self, attribute_name):
          '''
          Implemented attributes:
          * DNSName
          * LoadBalancerName
  
          Not implemented:
          * CanonicalHostedZoneID
          * LoadBalancerFullName
          * SecurityGroups
  
          This method is similar to models.py:FakeLoadBalancer.get_cfn_attribute()
          '''
          from moto.cloudformation.exceptions import UnformattedGetAttTemplateException
          not_implemented_yet = [
              'CanonicalHostedZoneID',
              'LoadBalancerFullName',
              'SecurityGroups',
          ]
          if attribute_name == 'DNSName':
              return self.dns_name
          elif attribute_name == 'LoadBalancerName':
              return self.name
          elif attribute_name in not_implemented_yet:
              raise NotImplementedError('"Fn::GetAtt" : [ "{0}" , "%s" ]"' % attribute_name)
          else:
              raise UnformattedGetAttTemplateException()
docs: Implemented attributes:
          * DNSName
          * LoadBalancerName
  
          Not implemented:
          * CanonicalHostedZoneID
          * LoadBalancerFullName
          * SecurityGroups
  
          This method is similar to models.py:FakeLoadBalancer.get_cfn_attribute()