code: @Override
      public DescribeCacheSecurityGroupsResult describeCacheSecurityGroups(DescribeCacheSecurityGroupsRequest request) {
          request = beforeClientExecution(request);
          return executeDescribeCacheSecurityGroups(request);
      }
docs: <p>
  Returns a list of cache security group descriptions. If a cache security group name is specified, the list
  contains only the description of that group.
  </p>
  
  @param describeCacheSecurityGroupsRequest
  Represents the input of a <code>DescribeCacheSecurityGroups</code> operation.
  @return Result of the DescribeCacheSecurityGroups operation returned by the service.
  @throws CacheSecurityGroupNotFoundException
  The requested cache security group name does not refer to an existing cache security group.
  @throws InvalidParameterValueException
  The value for a parameter is invalid.
  @throws InvalidParameterCombinationException
  Two or more incompatible parameters were specified.
  @sample AmazonElastiCache.DescribeCacheSecurityGroups
  @see <a href="http://docs.aws.amazon.com/goto/WebAPI/elasticache-2015-02-02/DescribeCacheSecurityGroups"
  target="_top">AWS API Documentation</a>