code: public ModelNode getDeploymentSubModel(final String subsystemName, final PathAddress address) {
          assert subsystemName != null : "The subsystemName cannot be null";
          assert address != null : "The address cannot be null";
          return getDeploymentSubModel(subsystemName, address, null, deploymentUnit);
      }
docs: Gets the sub-model for a components from the deployment itself. Operations, metrics and descriptions have to be
  registered as part of the subsystem registration {@link org.jboss.as.controller.ExtensionContext} and
  {@link org.jboss.as.controller.SubsystemRegistration#registerDeploymentModel(org.jboss.as.controller.ResourceDefinition)}.
  
  <p>
  The subsystem resource as well as each {@link org.jboss.as.controller.PathAddress#getParent()} parent element}
  from the address will be created if it does not already exist.
  </p>
  
  @param subsystemName the name of the subsystem
  @param address       the path address this sub-model should return the model for
  
  @return the model for the resource