def build_tree(path):
tree = Tree()
for basename, entry in trees[path].iteritems():
if type(entry) == dict:
mode = stat.S_IFDIR
sha = build_tree(os.path.join(path, basename))
else:
(mode, sha) = entry
tree.add(mode, basename, sha)
object_store.add_object(tree)
return tree.id
