[.] write README
[=] parse command
    [=] help
        [=] help comamnd
        [ ] help STRING command
    [=] attr
    [W] let
    [W] [ hash ] -> some thing will have error
    [W] interaction mode
    [W] exit
    [W] useful error msg
    [W] add -> new
[=] Sreach
[=] Sort(need I sort it...?)
[.] change class Value's name
[ ] use raise..catch statement
[.] do not make others use hash funtion of person -> should i?
    PersonPtr need -> ID
[ ] rename PersonPtr -> Person::Handle
[W] delete some using statement in header file.
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[ ] -> [.] -> [=] -> [W]

[W] A lot of Waring when make
[W] use for..begin..end statement instead of for &&[key, value]
[W] pertty output for person
[W] delete what you new
[W] Change
[W] Change person's Cls
[W] Delete
[W] use map instead of vector
[W] value: valid or invalid
[W] ID *(new: how about hash)*
[W] write to json file
[W] read from json file
[W] value's length should bigger than 0
[W] Classes Input
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[ ] -> [.] -> [=] -> [W]

feat: new feature
fix : fix bug
docs: about document
stl : code style
rfc : refactor code
test: about test
chor: about chore