window.
Shape:
      * Input: (N, C, L_{in}) or (C, L_{in}).
  * Output: (N, C, L_{out}) or (C, L_{out}), where

       L_{out} = \left\lfloor \frac{L_{in} + 2 \times
       \text{padding} - \text{dilation}       \times
       (\text{kernel\_size} - 1) - 1}{\text{stride}} +
       1\right\rfloor

Examples:
  >>> # pool of size=3, stride=2
  >>> m = nn.MaxPool1d(3, stride=2)
  >>> input = torch.randn(20, 16, 50)
  >>> output = m(input)
