How to use the yapf.yapflib.pytree_utils.GetNodeAnnotation function in yapf

def Visit_comp_for(self, node):  # pylint: disable=invalid-name
    # comp_for ::= 'for' exprlist 'in' testlist_safe [comp_iter]
    _AppendSubtypeRec(node, format_token.Subtype.COMP_FOR)
    # Mark the previous node as COMP_EXPR unless this is a nested comprehension
    # as these will have the outer comprehension as their previous node.
    attr = pytree_utils.GetNodeAnnotation(node.parent,
                                          pytree_utils.Annotation.SUBTYPE)
    if not attr or format_token.Subtype.COMP_FOR not in attr:
      _AppendSubtypeRec(node.parent.children[0], format_token.Subtype.COMP_EXPR)
    self.DefaultNodeVisit(node)

def _RecAnnotate(tree, annotate_name, annotate_value):
  """Recursively set the given annotation on all leafs of the subtree.

  Takes care to only increase the penalty. If the node already has a higher
  or equal penalty associated with it, this is a no-op.

  Args:
    tree: subtree to annotate
    annotate_name: name of the annotation to set
    annotate_value: value of the annotation to set
  """
  for child in tree.children:
    _RecAnnotate(child, annotate_name, annotate_value)
  if isinstance(tree, pytree.Leaf):
    cur_annotate = pytree_utils.GetNodeAnnotation(
        tree, annotate_name, default=0)
    if cur_annotate < annotate_value:
      pytree_utils.SetNodeAnnotation(tree, annotate_name, annotate_value)

def RecExpression(node, first_child_leaf):
    if node is first_child_leaf:
      return

    if isinstance(node, pytree.Leaf):
      if node.value in {'(', 'for'}:
        return
      penalty = pytree_utils.GetNodeAnnotation(
          node, pytree_utils.Annotation.SPLIT_PENALTY, default=0)
      _SetSplitPenalty(node, penalty + amt)
    else:
      for child in node.children:
        RecExpression(child, first_child_leaf)

def HasSubtype(node):
    """Return True if the arg list has a named assign subtype."""
    if isinstance(node, pytree.Leaf):
      return node_subtype in pytree_utils.GetNodeAnnotation(
          node, pytree_utils.Annotation.SUBTYPE, set())

    for child in node.children:
      node_name = pytree_utils.NodeName(child)
      if node_name not in {'atom', 'arglist', 'power'}:
        if HasSubtype(child):
          return True

    return False

def _MustBreakBefore(prev_token, cur_token):
  """Return True if a line break is required before the current token."""
  if prev_token.is_comment or (prev_token.previous_token and
                               prev_token.is_pseudo_paren and
                               prev_token.previous_token.is_comment):
    # Must break if the previous token was a comment.
    return True
  if (cur_token.is_string and prev_token.is_string and
      IsSurroundedByBrackets(cur_token)):
    # We want consecutive strings to be on separate lines. This is a
    # reasonable assumption, because otherwise they should have written them
    # all on the same line, or with a '+'.
    return True
  return pytree_utils.GetNodeAnnotation(
      cur_token.node, pytree_utils.Annotation.MUST_SPLIT, default=False)

def RecExpression(node, first_child_leaf):
    if node is first_child_leaf:
      return

    if isinstance(node, pytree.Leaf):
      if node.value in {'(', 'for', 'if'}:
        return
      penalty_annotation = pytree_utils.GetNodeAnnotation(
          node, pytree_utils.Annotation.SPLIT_PENALTY, default=0)
      if penalty_annotation < penalty:
        _SetSplitPenalty(node, penalty)
    else:
      for child in node.children:
        RecExpression(child, first_child_leaf)

def _DecrementSplitPenalty(node, amt):
  penalty = pytree_utils.GetNodeAnnotation(
      node, pytree_utils.Annotation.SPLIT_PENALTY, default=amt)
  penalty = penalty - amt if amt < penalty else 0
  _SetSplitPenalty(node, penalty)