def update_data(self):
        # Do nothing if there is no input and we aren't running.
        if len(self.inputs) == 0 or not self.running:
            return

        self.filter.update()
        # Propagate the data_changed event.
        self.data_changed = True
We just want to return a serialized formula object here.  Returning an object with
dataset/ETHPy150Open enthought/mayavi/mayavi/filters/filter_base.py/FilterBase.update_data--crossover with--dataset/ETHPy150Open stackdio/stackdio/stackdio/api/formulas/serializers.py/FormulaActionSerializer.to_representation