code: def _coerce_config_diff_command(data):
      if data is None or isinstance(data, dict):
          return data
      if isinstance(data, str):
          return {"default": data}
      log.warning(
          "unsupported configuration for diff command: %r", data
      )
      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 21 for calling a global function with example usage: _coerce_config_diff_command(data) and returns: None, data, dict