ProgramNode(0...31)(
  [:a],
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    [LocalVariableWriteNode(0...31)(
       :a,
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         [StringNode(13...25)(nil, (13...25), nil, "x\n" + "y\n" + "z\n")],
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       ),
       (0...1),
       (2...3)
     )]
  )
)
