# Codeblock 3 Outputafter pool        : torch.Size([1, 1, 4, 4])after flatten     : torch.Size([1, 16])after pool        : torch.Size([1, 1, 2, 2])after flatten     : torch.Size([1, 4])after pool        : torch.Size([1, 1, 1, 1])after flatten     : torch.Size([1, 1])after concatenate : torch.Size([1, 21])