returned tensor. Default: if "None", uses the current device
        for the default tensor type (see
        "torch.set_default_tensor_type()"). "device" will be the CPU
        for CPU tensor types and the current CUDA device for CUDA
        tensor types.
  * **requires_grad** (*bool**, **optional*) -- If autograd should
    record operations on the returned tensor. Default: "False".

Returns:
      A 1-D tensor of size (\text{window_length},) containing the
      window.
Return type:
      Tensor