docs: def do_dimension_name_list(mc, args):
      '''List names of metric dimensions.'''
      fields = {}
      if args.metric_name:
          fields['metric_name'] = args.metric_name
      if args.limit:
          fields['limit'] = args.limit
      if args.offset:
          fields['offset'] = args.offset
      if args.tenant_id:
          fields['tenant_id'] = args.tenant_id
  
      try:
          dimension_names = mc.metrics.list_dimension_names(**fields)
      except (osc_exc.ClientException, k_exc.HttpError) as he:
          raise osc_exc.CommandError('%s\n%s' % (he.message, he.details))
  
      if args.json:
          print(utils.json_formatter(dimension_names))
          return
  
      if isinstance(dimension_names, list):
          utils.print_list(dimension_names, ['Dimension Names'], formatters={
              'Dimension Names': lambda x: x['dimension_name']})