def concrete_forward(self, x: "torch.Tensor") -> "torch.Tensor":
        """
        Concrete forward pass through the convolutional layer

        :param x: concrete input to the convolutional layer.
        :return: concrete convolutional layer outputs.
        """
        x = self.conv(x)
        bias = torch.unsqueeze(self.bias, dim=-1)
        bias = torch.unsqueeze(bias, dim=-1)
        bias = torch.unsqueeze(bias, dim=0)
        return x + bias

        Concrete forward pass through the convolutional layer

        :param x: concrete input to the convolutional layer.
        :return: concrete convolutional layer outputs.
        
art/estimators/certification/deep_z/deep_z.py