{
    // As of now:
    "lines": {
        "a/b/c.py": [1, 2, 3, 4, 5],
        "a/b/d.py": [4, 5, 6, 7, 8],
    },
    "arcs": {
        "a/b/c.py: [[1, 2], [2, 3], [4, 5]],
    },
    "file_tracers": {
        "a/b/c.py": "fooey.plugin",
    },

    // We used to do this, but it got too bulky, removed in 4.0.1:
    "run" {
        "collector": "coverage.py 4.0",
        "config": {
            "branch": true,
            "source": ".",
        },
        "collected": "20150711T090600",
    },

    // Maybe in the future?
    "files": {
        "a/b/c.py": {
            "lines": [1, 2, 3, 4, 5],
            "arcs": [
                [1, 2], [3, 4], [5, -1],
            ],

            "plugin": "django.coverage",

            "lines": {
                "1": {
                    "tests": [
                        "foo/bar/test.py:TheTest.test_it",
                        "asdasdasd",
                        ],
                    "tests": [17, 34, 23, 12389],
                    },
                "2": {
                    "count": 23,
                    },
                "3": {},
                "4": {},
                "17": {},
                },

            "arcs": {
                "1.2": {},
                "2.3": {},
                "3.-1": {},
            },
        },
    },

    "tests": [
        {
            "file": "a/b/c.py",
            "test": "test_it",
            },
        {
            "file": "a/b/d.py",
            "test": "TheTest.test_it",
            },
    ],

    "runs": [
        {
            // info about each run?
            },
        { ... },
    ],
}