040000 tree 0990080502d01bc8be1687650a6ed57ce81b1e06	ccnping
040000 tree bbf0921f18306b4c96d6597a382e2fd7a2d46aef	ccnx
040000 tree 35cc195c8ef09e653eb609261b57fee910f5ea43	ndndump
040000 tree 9adafd8dec8b599caedd4b775104c65eb229b4be	py-pyccn