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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 _get_mod_mtime(self, filepath):
 """Gets the modified time of the file or its accompanying XML file, whichever is greater. """

        file_mtime = self.tramp.getmtime(filepath)        
        xmlpath = self.get_xmldoc_path(filepath)
        if self.tramp.exists(xmlpath):
            xml_mtime = self.tramp.getmtime(xmlpath)
            if xml_mtime > file_mtime:
                file_mtime = xml_mtime

        return file_mtime