code: def _is_unchanged(run_path, target_path, merge):
      """Returns True if a run path is unchanged in the target.
  
      Returns False if the merge is not configured with a target dir
      (i.e. `merge.target_dir` is None.
      """
      dest = os.path.join(merge.target_dir, target_path)
      if not os.path.isfile(dest):
          return False
      src = os.path.join(merge.run.dir, run_path)
      return not file_util.files_differ(src, dest)
  
imports: from collections import namedtuple
  import errno
  import fnmatch
  import logging
  import os
  import shutil
  from guild import file_util
  from guild import run_manifest
label_desc: Use image node_id 12 for calling a global function with example usage: _is_unchanged(run_path, target_path, merge) and returns: unknown, False