#!/usr/bin/python -uimport sysimport libxml2 #memory debug specificlibxml2.debugMemory(1) ## A document hosting the nodes returned from the extension function#mydoc = libxml2.newDoc("1.0") def foo(ctx, str):    global mydoc     #    # test returning a node set works as expected    #    parent = mydoc.newDocNode(None, 'p', None)    mydoc.addChild(parent)    node = mydoc.newDocText(str)    parent.addChild(node)    return [parent] doc = libxml2.parseFile("tst.xml")ctxt = doc.xpathNewContext()libxml2.registerXPathFunction(ctxt._o, "foo", None, foo)res = ctxt.xpathEval("foo('hello')")if type(res) != type([]):    print "Failed to return a nodeset"    sys.exit(1)if len(res) != 1:    print "Unexpected nodeset size"    sys.exit(1)node = res[0]if node.name != 'p':    print "Unexpected nodeset element result"    sys.exit(1)node = node.childrenif node.type != 'text':    print "Unexpected nodeset element children type"    sys.exit(1)if node.content != 'hello':    print "Unexpected nodeset element children content"    sys.exit(1) doc.freeDoc()mydoc.freeDoc()ctxt.xpathFreeContext() #memory debug specificlibxml2.cleanupParser()if libxml2.debugMemory(1) == 0:    print "OK"else:    print "Memory leak %d bytes" % (libxml2.debugMemory(1))    libxml2.dumpMemory()