{
    "$schema": "https://vega.github.io/schema/vega-lite/v4.json",
    "config": {
        "view": {
            "stroke": null
        }
    },
    "description": "Line drawn between airports in the U.S. simulating a flight itinerary",
    "height": 500,
    "layer": [
        {
            "data": {
                "format": {
                    "feature": "states",
                    "type": "topojson"
                },
                "url": "https://vega.github.io/vega-lite/data/us-10m.json"
            },
            "encoding": {
                "color": {
                    "value": "#eee"
                }
            },
            "mark": "geoshape"
        },
        {
            "data": {
                "url": "https://vega.github.io/vega-lite/data/airports.csv"
            },
            "encoding": {
                "color": {
                    "value": "gray"
                },
                "latitude": {
                    "field": "latitude",
                    "type": "quantitative"
                },
                "longitude": {
                    "field": "longitude",
                    "type": "quantitative"
                },
                "size": {
                    "value": 5
                }
            },
            "mark": "circle"
        },
        {
            "data": {
                "values": [
                    {
                        "airport": "SEA",
                        "order": 1
                    },
                    {
                        "airport": "SFO",
                        "order": 2
                    },
                    {
                        "airport": "LAX",
                        "order": 3
                    },
                    {
                        "airport": "LAS",
                        "order": 4
                    },
                    {
                        "airport": "DFW",
                        "order": 5
                    },
                    {
                        "airport": "DEN",
                        "order": 6
                    },
                    {
                        "airport": "ORD",
                        "order": 7
                    },
                    {
                        "airport": "JFK",
                        "order": 8
                    },
                    {
                        "airport": "ATL",
                        "order": 9
                    }
                ]
            },
            "encoding": {
                "latitude": {
                    "field": "latitude",
                    "type": "quantitative"
                },
                "longitude": {
                    "field": "longitude",
                    "type": "quantitative"
                },
                "order": {
                    "field": "order"
                }
            },
            "mark": "line",
            "transform": [
                {
                    "from": {
                        "data": {
                            "url": "https://vega.github.io/vega-lite/data/airports.csv"
                        },
                        "fields": [
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                            "longitude"
                        ],
                        "key": "iata"
                    },
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                }
            ]
        }
    ],
    "projection": {
        "type": "albersUsa"
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    "width": 800
}