{
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    "config": {
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            "gridWidth": 8
        },
        "axisX": {
            "gridColor": "red"
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            "legend": null,
            "type": "nominal"
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        "x": {
            "axis": {
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            },
            "field": "x",
            "type": "quantitative"
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            "axis": {
                "zindex": 1
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            "field": "y",
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    "mark": {
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        "size": 5000,
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}