# Codeblock 5b
    def forward(self, x, t):  #(1)
        print(f'images\t\t\t: {x.size()}')
        print(f'timesteps\t\t: {t.size()}, {t}')
        
        x = self.conv_0(x)  #(2)
        x = self.bn_0(x)    #(3)
        x = self.relu(x)    #(4)
        print(f'\nafter first conv\t: {x.size()}')
        
        time_embed = self.time_embedding()[t]      #(5)
        print(f'\ntime_embed\t\t: {time_embed.size()}')
        
        time_embed = self.linear(time_embed)       #(6)
        print(f'time_embed after linear\t: {time_embed.size()}')
        
        time_embed = time_embed[:, :, None, None]  #(7)
        print(f'time_embed expanded\t: {time_embed.size()}')
        
        x = x + time_embed  #(8)
        print(f'\nafter summation\t\t: {x.size()}')
        
        x = self.conv_1(x)  #(9)
        x = self.bn_1(x)    #(10)
        x = self.relu(x)    #(11)
        print(f'after second conv\t: {x.size()}')
        
        return x