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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(self, url_data):
 """Parse XML URL data."""

        self.url_data = url_data
        self.loc = False
        self.url = u""
        data = url_data.get_content()
        isfinal = True
        try:
            self.parser.Parse(data, isfinal)
        except ExpatError as expaterr:
            self.url_data.add_warning(expaterr.message,tag=WARN_XML_PARSE_ERROR)