for key in model.cv_results_:
    if key.startswith('param_'):
        # supported types should include all types, including bool, int float
        supported_types = (bool, int, float, six.string_types)
        if all(isinstance(i, supported_types) or i is None for i in model.cv_results_[key]):
            type = 'STRING'
        else:
            raise TypeError('Unsupported param type in param grid')

        # we renamed the attribute param to parameter, as this is a required
        # OpenML convention
        attribute = ("parameter_" + key[6:], type)
        trace_attributes.append(attribute)
return trace_attributes