Altair theme example

theme.py

def y_axis():
    return {
        "config": {
            "axisY": {
                "domain": False,
                "tickSize": 10,
                "gridDash": [2, 4]
            },
            "view": {
                "stroke": "transparent",
                # To keep the same height and width as the default theme:
                "continuousHeight": 300,
                "continuousWidth": 400,
            },
        }
    }