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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 attach_vpn_gateway(self, vpn_gateway_id, vpc_id):
 """ Attaches a VPN gateway to a VPC. :type vpn_gateway_id: str :param vpn_gateway_id: The ID of the vpn_gateway to attach :type vpc_id: str :param vpc_id: The ID of the VPC you want to attach the gateway to. :rtype: An attachment :return: a :class:`boto.vpc.vpngateway.Attachment` """

        params = {'VpnGatewayId': vpn_gateway_id,
                  'VpcId' : vpc_id}
        return self.get_object('AttachVpnGateway', params, Attachment)