code: def delete_all(self):
          '''
          Delete all keys
          '''
          for status, keys in six.iteritems(self.list_keys()):
              for key in keys:
                  try:
                      os.remove(os.path.join(self.opts['pki_dir'], status, key))
                      eload = {'result': True,
                               'act': 'delete',
                               'id': key}
                      self.event.fire_event(eload,
                                            salt.utils.event.tagify(prefix='key'))
                  except (OSError, IOError):
                      pass
          self.check_minion_cache()
          if self.opts.get('rotate_aes_key'):
              salt.crypt.dropfile(self.opts['cachedir'], self.opts['user'])
          return self.list_keys(f delete_all(self):
          '''
          Delete all keys
          '''
          for status, keys in six.iteritems(self.list_keys()):
              for key in keys:
                  try:
                      os.remove(os.path.join(self.opts['pki_dir'], status, key))
                      eload = {'result': True,
                               'act': 'delete',
                               'id': key}
                      self.event.fire_event(eload,
                                            salt.utils.event.tagify(prefix='key'))
                  except (OSError, IOError):
                      pass
          self.check_minion_cache()
          if self.opts.get('rotate_aes_key'):
              salt.crypt.dropfile(self.opts['cachedir'], self.opts['user'])
          return self.list_keys()
docs: Delete all keys