THIS IS A TEST INSTANCE. ALL YOUR CHANGES WILL BE LOST!!!!
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There could be cases where the the client side assignor can not compute a new assignment. For instance, in the context of Kafka Streams, the members may have a different topology. In this case, the client side assignor can return an error (PartitionAssignor.Assignment#error) to the group coordinator. In this case, the group coordinator automatically keeps the current target assignment for group.
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