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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 neighbor(self, **kwargs):
 """Experimental neighbor method. Args: ip_addr (str):
 IP Address of BGP neighbor. remote_as (str):
 Remote ASN of BGP neighbor. rbridge_id (str):
 The rbridge ID of the device on which BGP will be configured in a VCS fabric. afis (list):
 A list of AFIs to configure. Do not include IPv4 or IPv6 unicast as these are inferred from the `ip_addr` parameter. delete (bool):
 Deletes the neighbor if `delete` is ``True``. get (bool):
 Get config instead of editing config. (True, False) callback (function):
 A function executed upon completion of the method. The only parameter passed to `callback` will be the ``ElementTree`` `config`. Returns: Return value of `callback`. Raises: KeyError: if `remote_as` or `ip_addr` is not specified. Examples: """

        ip_addr = ip_interface(unicode(kwargs.pop('ip_addr')))
        rbridge_id = kwargs.pop('rbridge_id', '1')
        delete = kwargs.pop('delete', False)
        callback = kwargs.pop('callback', self._callback)
        remote_as = kwargs.pop('remote_as', None)
        get_config = kwargs.pop('get', False)
        if not get_config and remote_as is None:
            raise ValueError('When configuring a neighbor, you must specify '
                             'its remote-as.')
        neighbor_args = dict(router_bgp_neighbor_address=str(ip_addr.ip),
                             remote_as=remote_as,
                             rbridge_id=rbridge_id)
        if ip_addr.version == 6:
            neighbor_args['router_bgp_neighbor_ipv6_address'] = str(ip_addr.ip)

        neighbor, ip_addr_path = self._unicast_xml(ip_addr.version)
        config = neighbor(**neighbor_args)
        if ip_addr.version == 6 and not delete:
            config = self._build_ipv6(ip_addr, config, rbridge_id)

        if delete and config.find(ip_addr_path) is not None:
            if ip_addr.version == 4:
                config.find(ip_addr_path).set('operation', 'delete')
                config.find('.//*router-bgp-neighbor-address').set('operation',
                                                                   'delete')
            elif ip_addr.version == 6:
                config.find(ip_addr_path).set('operation', 'delete')
                config.find('.//*router-bgp-neighbor-ipv6-address').set(
                    'operation', 'delete')
        if get_config:
            return callback(config, handler='get_config')
        return callback(config)