code: def tags(cell):
      return cell["metadata"].get("tags", [])
  
imports: import argparse
  import copy
  import difflib
  import nbformat
  import re
  import shlex
  import subprocess
  import sys
  import os
  import tempfile
  from itertools import chain
  from traitlets import Set, Integer, Bool
  from traitlets.config import Config
  from pathlib import Path
  from nbconvert import NotebookExporter, HTMLExporter, writers, preprocessors
  from black import format_str, FileMode, InvalidInput
label_desc: Use image node_id 1 for calling the InsertTaggedCellsPreprocessor obj's underlying member method code with example usage: obj.tags(cell) and returns: cell