def values_to_pandas_dataframe(self) -> Optional[pd.DataFrame]:
    if ValueCollector.collect_values:
        columns = ['type', 'value']
        data = []
        for (function_name, value_collector) in self.value_collectors.items():
            for value in value_collector.values:
                data.append([function_name, value])
        df = pd.DataFrame(data=data, columns=columns)
        return df
    else:
        return None
def values_to_pandas_dataframe(self) -> Optional[pd.DataFrame]:
    if ValueCollector.collect_values:
        columns = ['type', 'value']
        data = []
        for (function_name, value_collector) in self.value_collectors.items():
            for value in value_collector.values:
                data.append([function_name, value])
        df = pd.DataFrame(data=data, columns=columns)
        return df
    else:
        return None