+ <eStructuralFeatures xsi:type="ecore:EAttribute" name="created" ordered="false"
+ lowerBound="1" eType="ecore:EDataType http://www.eclipse.org/emf/2002/Ecore#//EDate"
+ iD="true"/>
+ <eStructuralFeatures xsi:type="ecore:EAttribute" name="last_updated" ordered="false"
+ lowerBound="1" eType="ecore:EDataType http://www.eclipse.org/emf/2002/Ecore#//EDate"
+ iD="true"/>