fatal: Could not parse object '18f7b91345a2ce52eff3909cdb140fa625a4d47b'.
From https://github.com/NASA-Tensegrity-Robotics-Toolkit/NTRTsim
 * branch            master     -> FETCH_HEAD
HEAD is now at 18f7b91 Add explanation of new python specification
18f7b91345a2ce52eff3909cdb140fa625a4d47b