def forward(self, feats: Tuple[Tensor]) -> Tensor:
        """Forward the network. The input is multi scale feature maps and the
        output is the coordinates.

        Args:
            feats (Tuple[Tensor]): Multi scale feature maps.

        Returns:
            Tensor: output coordinates(and sigmas[optional]).
        """
        x = feats[-1]

        x = torch.flatten(x, 1)
        x = self.fc(x)

        return x.reshape(-1, self.num_joints, 4)
Forward the network. The input is multi scale feature maps and the
        output is the coordinates.

        Args:
            feats (Tuple[Tensor]): Multi scale feature maps.

        Returns:
            Tensor: output coordinates(and sigmas[optional]).
        
mmpose/mmpose/models/heads/regression_heads/rle_head.py