src/transformers/models/marian/convert_marian_to_pytorch.py/OpusState/_check_layer_entries
class OpusState:    def _check_layer_entries(self):
        self.encoder_l1 = self.sub_keys("encoder_l1")
        self.decoder_l1 = self.sub_keys("decoder_l1")
        self.decoder_l2 = self.sub_keys("decoder_l2")
        if len(self.encoder_l1) != 16:
            warnings.warn(f"Expected 16 keys for each encoder layer, got {len(self.encoder_l1)}")
        if len(self.decoder_l1) != 26:
            warnings.warn(f"Expected 26 keys for each decoder layer, got {len(self.decoder_l1)}")
        if len(self.decoder_l2) != 26:
            warnings.warn(f"Expected 26 keys for each decoder layer, got {len(self.decoder_l1)}")