# Codeblock 2b
    def forward(self, x):
        residual = x                 #(1)
        print(f'x & residual\t: {x.size()}')
        
        x = self.conv0(x)
        print(f'after conv0\t: {x.size()}')
        
        x = x.permute(0, 2, 3, 1)    #(2)
        print(f'after permute\t: {x.size()}')
        
        x = self.norm(x)
        print(f'after norm\t: {x.size()}')
        
        x = x.permute(0, 3, 1, 2)    #(3)
        print(f'after permute\t: {x.size()}')
        
        x = self.conv1(x)
        print(f'after conv1\t: {x.size()}')
        
        x = self.gelu(x)
        print(f'after gelu\t: {x.size()}')
        
        x = self.conv2(x)
        print(f'after conv2\t: {x.size()}')
        
        x = x + residual             #(4)
        print(f'after summation\t: {x.size()}')
        
        return x