integers holding how this "PackedSequence" is constructed from
        sequences.
  * **unsorted_indices** (*Tensor**, **optional*) -- Tensor of
    integers holding how this to recover the original sequences
    with correct order.

Note:
 "data" can be on arbitrary device and of arbitrary dtype.
 "sorted_indices" and "unsorted_indices" must be "torch.int64"
 tensors on the same device as "data".However, "batch_sizes"
 should always be a CPU "torch.int64" tensor.This invariant is
 maintained throughout "PackedSequence" class, and all functions
 that construct a *:class:PackedSequence* in PyTorch (i.e., they
 only pass in tensors conforming to this constraint).

batch_sizes: Tensor
  Alias for field number 1

count(value, /)
  Return number of occurrences of value.

data: Tensor
  Alias for field number 0

index(value, start=0, stop=9223372036854775807, /)
  Return first index of value.
