@SmithyInternalApi
    public static void overridePartitions(Partitions partitions) {
        PARTITIONS.clear();
        PARTITIONS.addAll(partitions.getPartitions());
        initializeRegionMap();
    }
Overrides the partitions provided by default. (changing this is not thread-safe).

@param partitions A list of partitions to set.
smithy-aws-endpoints/src/main/java/software/amazon/smithy/rulesengine/aws/language/functions/AwsPartition.java