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--Original document
<?xml version="1.0" encoding="utf-8"?>
<!-- Demonstration xml, parent element with two base classes-->
<config>
  <parent id="parent1">
    <item id="item1" name="Foo" attr="SomeOtherAttr"/>
  </parent>

  <child id="child1" inherits="parent1">
    <item1 id="item2" name="NewItem" someOtherAttr="YetMoreAttributes"/>
  </child>

  <complex>
    <child2 id="child2" inherits="parent1">
      <spoon id="spoon1" text="Silverspoon"></spoon>
    </child2>
  </complex>
</config>


--Transformed document
<?xml version="1.0" encoding="utf-8"?>
<parent id="parent1">
  <item id="item1" name="Foo" attr="SomeOtherAttr" />
</parent>
<child id="child1">
  <item1 id="item2" name="NewItem" someOtherAttr="YetMoreAttributes" />
  <item id="item1" name="Foo" attr="SomeOtherAttr" />
</child>
<complex>
  <child2 id="child2">
    <spoon id="spoon1" text="Silverspoon" />
    <item id="item1" name="Foo" attr="SomeOtherAttr" />
  </child2>
</complex>