cpython/Lib/test/xmltestdata/c14n-20/out_inNsSort_c14nDefault.xml

<a:foo xmlns:a="http://z3" xmlns:b="http://z2" xmlns:c="http://z1" c:att3="val3" b:att1="val1" b:att2="val2">
 <c:bar></c:bar>
 <c:bar xmlns:d="http://z0" d:att3="val3"></c:bar>
</a:foo>