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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 _vpc_config(self):
 """Get VPC config."""

        if self.vpc_enabled:
            subnets = get_subnets(env=self.env, region=self.region, purpose='internal')['subnet_ids'][self.region]
            security_groups = self._get_sg_ids()

            vpc_config = {'SubnetIds': subnets, 'SecurityGroupIds': security_groups}
        else:
            vpc_config = {'SubnetIds': [], 'SecurityGroupIds': []}
        LOG.debug("Lambda VPC config setup: %s", vpc_config)
        return vpc_config