def conv3x3(in_planes, out_planes, stride=1):
    '3x3 convolution with padding'
    return nn.Conv2d(in_planes, out_planes, kernel_size=3, stride=stride, padding=1, bias=False)
3x3 convolution with padding
def conv3x3(in_planes, out_planes, stride=1):
    
    return nn.Conv2d(in_planes, out_planes, kernel_size=3, stride=stride, padding=1, bias=False)