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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 redistribute(self, **kwargs):
 """Set BGP redistribute properties. Args: vrf (str):
 The VRF for this BGP process. rbridge_id (str):
 The rbridge ID of the device on which BGP will be configured in a VCS fabric. source (str):
 Source for redistributing. (connected) afi (str):
 Address family to configure. (ipv4, ipv6) 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 `source` is not specified. Examples: Traceback (most recent call last):
 KeyError Traceback (most recent call last):
 AttributeError Traceback (most recent call last):
 AttributeError """

        # This method is the same as the base method except for one place.
        # The class doesn't inherit from the base class, though, so we have
        # to duplicate.
        source = kwargs.pop('source')
        afi = kwargs.pop('afi', 'ipv4')
        callback = kwargs.pop('callback', self._callback)
        if afi not in ['ipv4', 'ipv6']:
            raise AttributeError('Invalid AFI.')
        args = dict(rbridge_id=kwargs.pop('rbridge_id', '1'),
                    afi=afi, source=source)
        redistribute = self._redistribute_builder(afi=afi, source=source)
        config = redistribute(**args)
        if kwargs.pop('get', False):
            return callback(config, handler='get_config')
        if kwargs.pop('delete', False):
            tag = 'redistribute-%s' % source
            config.find('.//*%s' % tag).set('operation', 'delete')
        return callback(config)