[
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  },
  {
    "x": 1,
    "Foo": 24,
    "Bar": 9
  }
]

<graph data="graphData">
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  <y field="y"></y>
  <graph-legend></graph-legend>
  <line field="for" value="Foo"></line>
  <line field="for" value="Bar"></line>
</graph>