code: @Override
      public SendInvitationResult sendInvitation(SendInvitationRequest request) {
          request = beforeClientExecution(request);
          return executeSendInvitation(request);
      }
docs: <p>
  Sends an enrollment invitation email with a URL to a user. The URL is valid for 72 hours or until you call this
  operation again, whichever comes first.
  </p>
  
  @param sendInvitationRequest
  @return Result of the SendInvitation operation returned by the service.
  @throws NotFoundException
  The resource is not found.
  @throws InvalidUserStatusException
  The attempt to update a user is invalid due to the user's current status.
  @throws ConcurrentModificationException
  There is a concurrent modification of resources.
  @sample AmazonAlexaForBusiness.SendInvitation
  @see <a href="http://docs.aws.amazon.com/goto/WebAPI/alexaforbusiness-2017-11-09/SendInvitation"
  target="_top">AWS API Documentation</a>