def bdev_zone_block_create(client, name, base_bdev, zone_capacity, optimal_open_zones):
    """Creates a virtual zone device on top of existing non-zoned bdev.

    Args:
        name: Zone device name
        base_bdev: Base Nvme bdev name
        zone_capacity: Surfaced zone capacity in blocks
        optimal_open_zones: Number of zones required to reach optimal write speed (optional, default: 1)

    Returns:
        Name of created block device.
    """
    params = {'name': name,
              'base_bdev': base_bdev,
              'zone_capacity': zone_capacity,
              'optimal_open_zones': optimal_open_zones}

    return client.call('bdev_zone_block_create', params)