code: def revoke(workers, qualification, by_name, reason, sandbox):
      
      if not (workers and qualification):
          raise click.BadParameter(
              "Must specify a qualification ID or name, and at least one worker ID"
          )
  
      mturk = _mturk_service_from_config(sandbox)
      if by_name:
          result = mturk.get_qualification_type_by_name(qualification)
          if result is None:
              raise click.BadParameter(
                  'No qualification with name "{}" exists.'.format(qualification)
              )
  
          qid = result["id"]
      else:
          qid = qualification
  
      if not click.confirm(
          '\n\nYou are about to revoke qualification "{}" '
          "for these workers:\n\t{}\n\n"
          "This will send an email to each of them from Amazon MTurk. "
          "Continue?".format(qid, "\n\t".join(workers))
      ):
          click.echo("Aborting...")
          return
  
      for worker in workers:
          if mturk.revoke_qualification(qid, worker, reason):
              click.echo(
                  'Revoked qualification "{}" from worker "{}"'.format(qid, worker)
              )
  
      # print out the current set of workers with the qualification
      results = list(mturk.get_workers_with_qualification(qid))
      click.echo(
          'There are now {} workers with qualification "{}"'.format(len(results), qid)
      )
docs: Revoke a qualification from 1 or more workers