(undo-tree-save-format-version . 1)
"c12ef913927758c9e0fba73bb5e37e98a8148bd6"
[nil nil nil nil (25162 15036 854058 109000) 0 nil]
([nil current ((1 . 2066) (t . 0)) nil (25162 15036 854053 220000) 0 nil])
nil