code: def diff(repo, *args, revs=None, experiment=False, **kwargs):
      if repo.scm.no_commits:
          return {}
      return repo.plots.show(
          *args, revs=_revisions(repo, revs, experiment), **kwargs
      )
  
label_desc: Use image node_id 2 for calling a global function with example usage: diff(repo) and returns: repo, dict