def to_serializable(self, obj, name, val):
        d = super(UnitsSpec, self).to_serializable(obj, name, val)
        if d is not None and d not in 'units':
            d["units"] = getattr(obj, name+"_units")
        return d
dataset/ETHPy150Open bokeh/bokeh/bokeh/core/properties.py/UnitsSpec.to_serializable/swapped operands of `not in`