code: def _diff_run_dir_base(ctx):
      from . import diff_impl
  
      args = click_util.Args(**ctx.params)
      if args.dir:
          return os.path.abspath(args.dir)
      run = _run_to_diff(ctx)
      if not run:
          return None
      if args.working:
          return ac_support.ac_safe_apply(
              diff_impl._working_dir_for_run, [run]
          )
      if args.sourcecode:
          return _sourcecode_dir(run)
      return run.dir
  
file_path: guildai/guild/commands/runs_diff.py
imports: import os
  import click
  from guild import click_util
  from .None import ac_support
  from .None import remote_support
  from .None import runs_support
label_desc: Use image node_id 5 for calling a global function with example usage: _diff_run_dir_base(ctx) and returns: run, os, None, ac_support, _sourcecode_dir