(undo-tree-save-format-version . 1)
"d588b4ab7900325f2d58d463abcbf0d9bbea7f7c"
[nil nil nil nil (25197 28317 926989 943000) 0 nil]
([nil current ((1 . 3896) (t . 0)) nil (25197 28317 926985 635000) 0 nil])
nil