def METHOD_NAME(self) -> FlaskResponse:
    """
    Get the form_data stored in the database for existing slice.
    params: slice_id: integer
    """
    form_data = {}
    if slice_id := request.args.get("slice_id"):
        slc = db.session.query(Slice).filter_by(id=slice_id).one_or_none()
        if slc:
            form_data = slc.form_data.copy()
    update_time_range(form_data)
    return self.json_response(form_data)