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

def DefaultNodeVisit(self, node):
    """Override the default visitor for Node.

    This will set the blank lines required if the last entity was a class or
    function.

    Arguments:
      node: (pytree.Node) The node to visit.
    """
    if self.last_was_class_or_function:
      if pytree_utils.NodeName(node) in _PYTHON_STATEMENTS:
        leaf = _GetFirstChildLeaf(node)
        self._SetNumNewlines(leaf, self._GetNumNewlines(leaf))
    self.last_was_class_or_function = False
    super(_BlankLineCalculator, self).DefaultNodeVisit(node)

def Visit_async_funcdef(self, node):  # pylint: disable=invalid-name
    self._StartNewLine()
    index = 0
    for child in node.children:
      index += 1
      self.Visit(child)
      if pytree_utils.NodeName(child) == 'ASYNC':
        break
    for child in node.children[index].children:
      self.Visit(child)

def Visit_atom(self, node):  # pylint: disable=invalid-name
    for child in node.children:
      self.Visit(child)

    if len(node.children) != 3:
      return
    if pytree_utils.NodeName(node.children[0]) != 'LPAR':
      return

    for child in node.children[1].children:
      pytree_utils.SetOpeningBracket(
          pytree_utils.FirstLeafNode(child), node.children[0])

def Visit(self, node):
    """Visit a node."""
    method = 'Visit_{0}'.format(pytree_utils.NodeName(node))
    if hasattr(self, method):
      # Found a specific visitor for this node
      getattr(self, method)(node)
    else:
      if isinstance(node, pytree.Leaf):
        self.DefaultLeafVisit(node)
      else:
        self.DefaultNodeVisit(node)

def _AsyncFunction(node):
  return (py3compat.PY3 and node.prev_sibling and
          pytree_utils.NodeName(node.prev_sibling) == 'ASYNC')

def _HasPrecedence(tok):
  """Whether a binary operation has precedence within its context."""
  node = tok.node

  # We let ancestor be the statement surrounding the operation that tok is the
  # operator in.
  ancestor = node.parent.parent

  while ancestor is not None:
    # Search through the ancestor nodes in the parse tree for operators with
    # lower precedence.
    predecessor_type = pytree_utils.NodeName(ancestor)
    if predecessor_type in ['arith_expr', 'term']:
      # An ancestor "arith_expr" or "term" means we have found an operator
      # with lower precedence than our tok.
      return True
    if predecessor_type != 'atom':
      # We understand the context to look for precedence within as an
      # arbitrary nesting of "arith_expr", "term", and "atom" nodes. If we
      # leave this context we have not found a lower precedence operator.
      return False
    # Under normal usage we expect a complete parse tree to be available and
    # we will return before we get an AttributeError from the root.
    ancestor = ancestor.parent

def _FindNodeWithStandaloneLineParent(node):
  """Find a node whose parent is a 'standalone line' node.

  See the comment above _STANDALONE_LINE_NODES for more details.

  Arguments:
    node: node to start from

  Returns:
    Suitable node that's either the node itself or one of its ancestors.
  """
  if pytree_utils.NodeName(node.parent) in _STANDALONE_LINE_NODES:
    return node
  else:
    # This is guaranteed to terminate because 'file_input' is the root node of
    # any pytree.
    return _FindNodeWithStandaloneLineParent(node.parent)

def _DetermineMustSplitAnnotation(node):
  """Enforce a split in the list if the list ends with a comma."""
  if style.Get('DISABLE_ENDING_COMMA_HEURISTIC'):
    return
  if not _ContainsComments(node):
    token = next(node.parent.leaves())
    if token.value == '(':
      if sum(1 for ch in node.children
             if pytree_utils.NodeName(ch) == 'COMMA') < 2:
        return
    if (not isinstance(node.children[-1], pytree.Leaf) or
        node.children[-1].value != ','):
      return
  num_children = len(node.children)
  index = 0
  _SetMustSplitOnFirstLeaf(node.children[0])
  while index < num_children - 1:
    child = node.children[index]
    if isinstance(child, pytree.Leaf) and child.value == ',':
      next_child = node.children[index + 1]
      if next_child.type == grammar_token.COMMENT:
        index += 1
        if index >= num_children - 1:
          break
      _SetMustSplitOnFirstLeaf(node.children[index + 1])

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

  if not HasSubtype(node):
    return

  for child in node.children:
    node_name = pytree_utils.NodeName(child)
    if node_name not in {'atom', 'COMMA'}:
      _AppendFirstLeafTokenSubtype(child, list_subtype)