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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 get_vpc_config(self, vpc_config_override=vpc_utils.VPC_CONFIG_DEFAULT):
 """ Returns VpcConfig dict either from this Estimator's subnets and security groups, or else validate and return an optional override value. """

        if vpc_config_override is vpc_utils.VPC_CONFIG_DEFAULT:
            return vpc_utils.to_dict(self.subnets, self.security_group_ids)
        else:
            return vpc_utils.sanitize(vpc_config_override)