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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 diff_config(self, second_host, mode='stanza'):
 """ Generate configuration differences with a second device. Purpose: Open a second ncclient.manager.Manager with second_host, and | and pull the configuration from it. We then use difflib to | get the delta between the two, and yield the results. @param second_host: the IP or hostname of the second device to | compare against. @type second_host: str @param mode: string to signify 'set' mode or 'stanza' mode. @type mode: str @returns: iterable of strings @rtype: str """

        second_conn = manager.connect(
            host=second_host,
            port=self.port,
            username=self.username,
            password=self.password,
            timeout=self.connect_timeout,
            device_params={'name': 'junos'},
            hostkey_verify=False
        )

        command = 'show configuration'
        if mode == 'set':
            command += ' | display set'

        # get the raw xml config
        config1 = self._session.command(command, format='text')
        # for each /configuration-output snippet, turn it to text and join them
        config1 = ''.join([snippet.text.lstrip('\n') for snippet in
                          config1.xpath('//configuration-output')])

        config2 = second_conn.command(command, format='text')
        config2 = ''.join([snippet.text.lstrip('\n') for snippet in
                          config2.xpath('//configuration-output')])

        return difflib.unified_diff(config1.splitlines(), config2.splitlines(),
                                    self.host, second_host)