code: function buildNatGateway(position, zone) {
    const cfName = `NatGateway${position}`;
    return {
      [cfName]: {
        Type: 'AWS::EC2::NatGateway',
        Properties: {
          AllocationId: {
            'Fn::GetAtt': [`EIP${position}`, 'AllocationId'],
          },
          SubnetId: {
            Ref: `${PUBLIC_SUBNET}Subnet${position}`,
          },
          Tags: [
            {
              Key: 'Name',
              Value: {
                'Fn::Join': [
                  '-',
                  [
                    {
                      Ref: 'AWS::StackName',
                    },
                    zone,
                  ],
                ],
              },
            },
          ],
        },
      },
    };
  }
docs: Build a NatGateway in a given AZ
  
  @param {Number} position
  @param {String} zone
  @return {Object}