code: def _format_sha1(graph, node):
      
      try:
          submodules = node.submodules
  
          if submodules:
              submodule = ':'.join(submodules)
              return click.style(submodule, fg='green') + '@' + click.style(
                  node.commit.hexsha[:8], fg='yellow'
              )
      except KeyError:
          pass
      return click.style(node.commit.hexsha[:8], fg='yellow')
docs: Return formatted text with the submodule information.