o  9:72902de1ba45 +tag topic -> 3256c19d708b
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o   |  8:efde33cd0b66 (topic) +tag v1 -> fa7ad5b80a88
|   |
| o |  7:210d711041da (topic2) +tag v1 -> b86ee8b83781
| | |
| o |  6:b86ee8b83781 (topic2)
| | |
| | o  5:3256c19d708b +tag v4 -> f7fbcc489e40
| | |
| | o  4:f7fbcc489e40
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o |    3:fa7ad5b80a88 (topic) +tag v1 -> 6c3929c66c32
| |
o |    2:6c3929c66c32 (topic)
|/
o      1:b6e596caff9d +tag v1 -> 1ecfad722425
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o      0:1ecfad722425