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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_commands_from_xml(self, mission, role):
 """Get commands from etree"""

        handlers = mission.findall(CommandParser.ns + "AgentSection" + "/" + CommandParser.ns + "AgentHandlers")
        if len(handlers) <= role:
            raise CommandHandlerException("Not enough agents sections in XML")
        commands = []
        self._command_hander(handlers[role], False, commands)
        return commands