private VerifyAssignmentResult runVerifyAssignment(Admin admin,
                                                       String jsonString,
                                                       Boolean preserveThrottles) {
        try {
            return verifyAssignment(admin, jsonString, preserveThrottles);
        } catch (ExecutionException | InterruptedException | JsonProcessingException e) {
            throw new RuntimeException(e);
        }
    }
Describe the broker-level throttles in the cluster.

@return                A map whose keys are broker IDs and whose values are throttle
                       information.  The nested maps are keyed on throttle name.
tools/src/test/java/org/apache/kafka/tools/reassign/ReassignPartitionsCommandTest.java