code: def _default_diff_cmd_for_path(path):
      if not path:
          return None
      _root, ext = os.path.splitext(path)
      if ext == ".ipynb":
          return _find_cmd(["nbdiff-web -M"])
      return None
  
imports: import logging
  import os
  import re
  import subprocess
  from guild import cli
  from guild import click_util
  from guild import cmd_impl_support
  from guild import config
  from guild import run_util
  from guild import util
  from .None import remote_impl_support
  from .None import runs_impl
label_desc: Use image node_id 23 for calling a global function with example usage: _default_diff_cmd_for_path(path) and returns: None, None, _find_cmd