<superblock uuid="" time="1" transaction="0" data_block_size="128">
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    <range_mapping origin_begin="0" data_begin="0" length="16384" time="0"/>
  </device>
  <device dev_id ="1" mapped_blocks="16384" transaction="0" creation_time="1" snap_time="1">
    <range_mapping origin_begin="0" data_begin="16384" length="16384" time="1"/>
  </device>
</superblock>
