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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 search_tor_node(self, data_type, data):
 """Lookup an artifact to check if it is a known tor exit node. :param data_type: The artifact type. Must be one of 'ip', 'fqdn' or 'domain' :param data: The artifact to lookup :type data_type: str :type data: str :return: Data relative to the tor node. If the looked-up artifact is related to a tor exit node it will contain a `nodes` array. That array will contains a list of nodes containing the following keys: - name: name given to the router - ip: their IP address - hostname: Hostname of the router - country_code: ISO2 code of the country hosting the router - as_name: ASName registering the router - as_number: ASNumber registering the router Otherwise, `nodes` will be empty. :rtype: list """

        results = []
        if data_type == 'ip':
            results = self._get_node_from_ip(data)
        elif data_type == 'fqdn':
            results = self._get_node_from_fqdn(data)
        elif data_type == 'domain':
            results = self._get_node_from_domain(data)
        else:
            pass
        return {"nodes": results}