message: [docs] Adds spacing between sections to fix docs for weighted_cross_entropy_with_logits
diff: @@ -330,9 +330,12 @@ def weighted_cross_entropy_with_logits(labels=None,
  This is like `sigmoid_cross_entropy_with_logits()` except that `pos_weight`,
  allows one to trade off recall and precision by up- or down-weighting the
  cost of a positive error relative to a negative error.
  +
  The usual cross-entropy cost is defined as:
  +
  labels * -log(sigmoid(logits)) +
  (1 - labels) * -log(1 - sigmoid(logits))
  +
  A value `pos_weight > 1` decreases the false negative count, hence increasing
  the recall.
  Conversely setting `pos_weight < 1` decreases the false positive count and
  @@ -340,20 +343,27 @@ def weighted_cross_entropy_with_logits(labels=None,
  This can be seen from the fact that `pos_weight` is introduced as a
  multiplicative coefficient for the positive labels term
  in the loss expression:
  +
  labels * -log(sigmoid(logits)) * pos_weight +
  (1 - labels) * -log(1 - sigmoid(logits))
  +
  For brevity, let `x = logits`, `z = labels`, `q = pos_weight`.
  The loss is:
  +
  qz * -log(sigmoid(x)) + (1 - z) * -log(1 - sigmoid(x))
  = qz * -log(1 / (1 + exp(-x))) + (1 - z) * -log(exp(-x) / (1 + exp(-x)))
  = qz * log(1 + exp(-x)) + (1 - z) * (-log(exp(-x)) + log(1 + exp(-x)))
  = qz * log(1 + exp(-x)) + (1 - z) * (x + log(1 + exp(-x))
  = (1 - z) * x + (qz + 1 - z) * log(1 + exp(-x))
  = (1 - z) * x + (1 + (q - 1) * z) * log(1 + exp(-x))
  +
  Setting `l = (1 + (q - 1) * z)`, to ensure stability and avoid overflow,
  the implementation uses
  +
  (1 - z) * x + l * (log(1 + exp(-abs(x))) + max(-x, 0))
  +
  `logits` and `labels` must have the same type and shape.
  +
  Args:
  labels: A `Tensor` of the same type and shape as `logits`.
  logits: A `Tensor` of type `float32` or `float64`.
  @@ -364,6 +374,7 @@ def weighted_cross_entropy_with_logits(labels=None,
  Returns:
  A `Tensor` of the same shape as `logits` with the componentwise
  weighted logistic losses.
  +
  Raises:
  ValueError: If `logits` and `labels` do not have the same shape.
  """
  