code: @Override
      public AssociateSubnetCidrBlockResult associateSubnetCidrBlock(AssociateSubnetCidrBlockRequest request) {
          request = beforeClientExecution(request);
          return executeAssociateSubnetCidrBlock(request);
      }
docs: <p>
  Associates a CIDR block with your subnet. You can only associate a single IPv6 CIDR block with your subnet. An
  IPv6 CIDR block must have a prefix length of /64.
  </p>
  
  @param associateSubnetCidrBlockRequest
  @return Result of the AssociateSubnetCidrBlock operation returned by the service.
  @sample AmazonEC2.AssociateSubnetCidrBlock
  @see <a href="http://docs.aws.amazon.com/goto/WebAPI/ec2-2016-11-15/AssociateSubnetCidrBlock" target="_top">AWS
  API Documentation</a>