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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def parse_string(self, xmlstr, initialize=True):
 """ Load manifest from XML string """

        try:
            domtree = minidom.parseString(xmlstr)
        except xml.parsers.expat.ExpatError, e:
            raise ManifestXMLParseError(e)
        self.load_dom(domtree, initialize)