src/transformers/models/dpr/modeling_dpr.py/DPRSpanPredictor/__init__
class DPRSpanPredictor:    def __init__(self, config: DPRConfig):
        super().__init__(config)
        self.encoder = DPREncoder(config)
        self.qa_outputs = nn.Linear(self.encoder.embeddings_size, 2)
        self.qa_classifier = nn.Linear(self.encoder.embeddings_size, 1)
        # Initialize weights and apply final processing
        self.post_init()