doc:   [
    DocGroup({"tag": "bullet"}, [
        DocGroup({"tag": "pre"}, [
            DocGroup({"client": "e", "tag": "caret"}, [])
        ])
    ]),
    DocGroup({"tag": "h1"}, [
        DocChars("T0"), DocGroup({"client": "h", "tag": "caret"}, []),
        DocChars("5"), DocGroup({"tag": "caret", "client": "f"}, []),
        DocChars("3 "), DocGroup({"client": "g", "tag": "caret"}, [])
    ]),
    DocGroup({"tag": "h1"}, [
        DocChars("Ej"), DocGroup({"tag": "caret", "client": "c"}, [])
    ]),
    DocGroup({"tag": "pre"}, [
        DocChars("m1 f")
    ]),
    DocGroup({"tag": "pre"}, [
        DocChars(" c  ")
    ]),
    DocGroup({"tag": "bullet"}, [
        DocGroup({"tag": "h2"}, [
            DocChars(" O")
        ]),
        DocGroup({"tag": "h2"}, [
            DocGroup({"tag": "caret", "client": "b"}, []),
            DocChars(" "), DocGroup({"client": "a", "tag": "caret"}, []),
            DocChars("2  U j6O1pT8vr"), DocGroup({"tag": "caret", "client": "d"}, []),
            DocChars("\'s up with you?")
        ])
    ])
]

a_del: [
    DelWithGroup([
        DelGroup([
            DelGroup([])
        ])
    ]),
    DelGroup([
        DelSkip(2), DelWithGroup([]),
        DelSkip(1), DelGroup([]),
        DelChars(1), DelSkip(1), DelWithGroup([])
    ]),
    DelGroup([
        DelChars(2), DelGroup([])
    ]),
    DelWithGroup([
        DelSkip(4)
    ]),
    DelGroup([
        DelSkip(3), DelChars(1)
    ]),
    DelGroup([
        DelGroup([
            DelChars(2)
        ]),
        DelGroup([
            DelGroup([]),
            DelSkip(1), DelGroup([]),
            DelSkip(13), DelChars(1), DelGroup([]),
            DelSkip(15)
        ])
    ])
]
a_add: [
    AddWithGroup([
        AddGroup({"tag": "pre"}, [
            AddGroup({"client": "e", "tag": "caret"}, []),
            AddChars("t")
        ])
    ]),
    AddGroup({"tag": "h1"}, [
        AddSkip(2), AddWithGroup([]),
        AddSkip(1), AddChars("U"), AddGroup({"client": "f", "tag": "caret"}, []),
        AddSkip(1), AddWithGroup([]),
        AddGroup({"client": "c", "tag": "caret"}, []),
        AddChars(" ")
    ]),
    AddWithGroup([
        AddSkip(4)
    ]),
    AddGroup({"tag": "pre"}, [
        AddGroup({"tag": "caret", "client": "a"}, []),
        AddSkip(3), AddChars("7 "), AddGroup({"client": "b", "tag": "caret"}, []),
        AddChars(" "), AddGroup({"client": "d", "tag": "caret"}, []),
        AddSkip(29)
    ])
]

b_del: [
    DelWithGroup([
        DelWithGroup([
            DelWithGroup([])
        ])
    ]),
    DelGroup([
        DelSkip(2), DelWithGroup([]),
        DelSkip(1), DelWithGroup([]),
        DelSkip(1), DelChars(1), DelGroup([])
    ]),
    DelWithGroup([
        DelChars(1)
    ])
]
b_add: [
    AddWithGroup([
        AddWithGroup([
            AddWithGroup([])
        ])
    ]),
    AddGroup({"tag": "p"}, [
        AddSkip(2), AddWithGroup([]),
        AddSkip(1), AddWithGroup([]),
        AddSkip(1), AddChars("Q")
    ]),
    AddWithGroup([
        AddChars("l"), AddGroup({"client": "g", "tag": "caret"}, [])
    ])
]