code: @Override
      public DeregisterTaskDefinitionResult deregisterTaskDefinition(DeregisterTaskDefinitionRequest request) {
          request = beforeClientExecution(request);
          return executeDeregisterTaskDefinition(request);
      }
docs: <p>
  Deregisters the specified task definition by family and revision. Upon deregistration, the task definition is
  marked as <code>INACTIVE</code>. Existing tasks and services that reference an <code>INACTIVE</code> task
  definition continue to run without disruption. Existing services that reference an <code>INACTIVE</code> task
  definition can still scale up or down by modifying the service's desired count.
  </p>
  <p>
  You cannot use an <code>INACTIVE</code> task definition to run new tasks or create new services, and you cannot
  update an existing service to reference an <code>INACTIVE</code> task definition. However, there may be up to a
  10-minute window following deregistration where these restrictions have not yet taken effect.
  </p>
  <note>
  <p>
  At this time, <code>INACTIVE</code> task definitions remain discoverable in your account indefinitely. However,
  this behavior is subject to change in the future, so you should not rely on <code>INACTIVE</code> task
  definitions persisting beyond the lifecycle of any associated tasks and services.
  </p>
  </note>
  
  @param deregisterTaskDefinitionRequest
  @return Result of the DeregisterTaskDefinition operation returned by the service.
  @throws ServerException
  These errors are usually caused by a server issue.
  @throws ClientException
  These errors are usually caused by a client action, such as using an action or resource on behalf of a
  user that doesn't have permissions to use the action or resource, or specifying an identifier that is not
  valid.
  @throws InvalidParameterException
  The specified parameter is invalid. Review the available parameters for the API request.
  @sample AmazonECS.DeregisterTaskDefinition
  @see <a href="http://docs.aws.amazon.com/goto/WebAPI/ecs-2014-11-13/DeregisterTaskDefinition" target="_top">AWS
  API Documentation</a>