code: def _quote_label(node):
      label = str(node)
      # Node names should not contain ":" unless they are quoted with "".
      # See: https://github.com/pydot/pydot/issues/258.
      if label[0] != '"' and label[-1] != '"':
          return f'"{label}"'
      return label
  
file_path: dvc/dvc/commands/dag.py
imports: from typing import TYPE_CHECKING
  from dvc.cli import formatter
  from dvc.cli.command import CmdBase
  from dvc.cli.utils import append_doc_link
  from dvc.ui import ui
label_desc: Use image node_id 2 for calling a global function with example usage: _quote_label(node) and returns: label, str, label, str