(undo-tree-save-format-version . 1)
"8d94c5aa59977033275c493b1a04569b0509ab90"
[nil nil nil nil (25164 52796 515403 222000) 0 nil]
([nil current ((1 . 2417) (t . 0)) nil (25164 52796 515398 974000) 0 nil])
nil