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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def conv3x3(in_channels, out_channels, stride=1):
 """ 3x3 convolution with padding. Original code has had bias turned off, because Batch Norm would remove the bias either way """

    return nn.Conv2d(in_channels, out_channels, kernel_size=3, stride=stride, padding=1, bias=False)