code: def edit(dataset_uri):
      
      try:
          dataset = dtoolcore.ProtoDataSet.from_uri(
              uri=dataset_uri,
              config_path=CONFIG_PATH
          )
      except dtoolcore.DtoolCoreTypeError:
          dataset = dtoolcore.DataSet.from_uri(
              uri=dataset_uri,
              config_path=CONFIG_PATH
          )
      readme_content = dataset.get_readme_content()
  
      try:
          # Python2 compatibility.
          readme_content = unicode(readme_content, "utf-8")
      except NameError:
          pass
  
      edited_content = click.edit(readme_content)
      if edited_content is not None:
          _validate_and_put_readme(dataset, edited_content)
          click.secho("Updated readme ", nl=False, fg="green")
      else:
          click.secho("Did not update readme ", nl=False, fg="red")
      click.secho(dataset_uri)
docs: Default editor updating of readme content.