code: public ReadOperation<BsonDocument> asExplainableOperation(final ExplainVerbosity explainVerbosity) {
          return new AggregateExplainOperation(namespace, pipeline)
                  .allowDiskUse(allowDiskUse)
                  .maxTime(maxTimeMS, TimeUnit.MILLISECONDS)
                  .hint(hint);
      }
docs: Gets an operation whose execution explains this operation.
  
  @param explainVerbosity the explain verbosity
  @return a read operation that when executed will explain this operation