040000 tree 8804fb9c1210964a2ade82d361e684e0f7415ba9	ccnping
040000 tree 32008ea7142d15e39b25a0d8a16b69d5092280d2	ccnx
040000 tree e897d0a2b949ded56d519002d8e4fdcb6f4fb3d2	ndndump
040000 tree 9adafd8dec8b599caedd4b775104c65eb229b4be	py-pyccn