src/transformers/feature_extraction_sequence_utils.py/SequenceFeatureExtractor/__init__
class SequenceFeatureExtractor:    def __init__(self, feature_size: int, sampling_rate: int, padding_value: float, **kwargs):
        self.feature_size = feature_size
        self.sampling_rate = sampling_rate
        self.padding_value = padding_value

        self.padding_side = kwargs.pop("padding_side", "right")
        self.return_attention_mask = kwargs.pop("return_attention_mask", True)

        super().__init__(**kwargs)