@ ProgramNode (location: (0...11))
├── locals: []
└── statements:
    @ StatementsNode (location: (0...11))
    └── body: (length: 1)
        └── @ HashNode (location: (0...11))
            ├── opening_loc: (0...1) = "{"
            ├── elements: (length: 1)
            │   └── @ AssocNode (location: (2...9))
            │       ├── key:
            │       │   @ SymbolNode (location: (2...6))
            │       │   ├── opening_loc: (2...3) = "'"
            │       │   ├── value_loc: (3...4) = "a"
            │       │   ├── closing_loc: (4...6) = "':"
            │       │   └── unescaped: "a"
            │       ├── value:
            │       │   @ SymbolNode (location: (7...9))
            │       │   ├── opening_loc: (7...8) = ":"
            │       │   ├── value_loc: (8...9) = "b"
            │       │   ├── closing_loc: ∅
            │       │   └── unescaped: "b"
            │       └── operator_loc: ∅
            └── closing_loc: (10...11) = "}"
