length
  * Output: (N, C) or (N, C, L) (same shape as input)

Examples:
  >>> # With Learnable Parameters
  >>> m = nn.BatchNorm1d(100)
  >>> # Without Learnable Parameters
  >>> m = nn.BatchNorm1d(100, affine=False)
  >>> input = torch.randn(20, 100)
  >>> output = m(input)
