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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 set_symbol(self, symbol):
 """ Set a symbol for a device :param str symbol: Symbol to use """

        if symbol == 'EtherSwitch router':
            symbol = 'multilayer_switch'
        elif symbol == 'Host':
            symbol = 'computer'

        normal = ':/symbols/%s.normal.svg' % symbol
        selected = ':/symbols/%s.selected.svg' % symbol

        self.node['default_symbol'] = normal
        self.node['hover_symbol'] = selected