Thanks for your response. So I changed it to
self.layer_attend1 =  nn.Sequential(nn.Conv2d(64, 64, stride=2, padding=1, kernel_size=3),
                                                         nn.AdaptiveAvgPool2d(1),
                                                         nn.Softmax(1))

Do you think if it is wrong or could you please show how to fill the args of nn.Conv2d(64, 64, stride=2, padding=1, kernel_size=3) otherwise?