message: softmax_cross_entropy: Improve docstring
  Improve docstring of `softmax_cross_entropy`.
diff: @@ -652,7 +652,7 @@ def softmax_cross_entropy(
  Args:
  onehot_labels: `[batch_size, num_classes]` target one-hot-encoded labels.
  - logits: [batch_size, num_classes] logits outputs of the network .
  + logits: `[batch_size, num_classes]` logits outputs of the network .
  weights: Optional `Tensor` whose rank is either 0, or rank 1 and is
  broadcastable to the loss which is a `Tensor` of shape `[batch_size]`.
  label_smoothing: If greater than 0 then smooth the labels.
  