---------- Input ----------
 {  } 
---------- Output ---------
{}
---------- AST ------------
KeyPaths {
    paths: [],
}


---------- Input ----------
 { 1, a } 
---------- Output ---------
{1,a}
---------- AST ------------
KeyPaths {
    paths: [
        Index(
            1,
        ),
        Name(
            "a",
        ),
    ],
}


---------- Input ----------
{1,a,-2}
---------- Output ---------
{1,a,-2}
---------- AST ------------
KeyPaths {
    paths: [
        Index(
            1,
        ),
        Name(
            "a",
        ),
        Index(
            -2,
        ),
    ],
}


---------- Input ----------
{a,"b","c"} 
---------- Output ---------
{a,"b","c"}
---------- AST ------------
KeyPaths {
    paths: [
        Name(
            "a",
        ),
        QuotedName(
            "b",
        ),
        QuotedName(
            "c",
        ),
    ],
}