docs: def __get_request_auth(username, password):
      '''
      Get libvirt.openAuth callback with username, password values overriding
      the configuration ones.
      '''
  
      # pylint: disable=unused-argument
      def __request_auth(credentials, user_data):
          '''Callback method passed to libvirt.openAuth().
  
          The credentials argument is a list of credentials that libvirt
          would like to request. An element of this list is a list containing
          5 items (4 inputs, 1 output):
            - the credential type, e.g. libvirt.VIR_CRED_AUTHNAME
            - a prompt to be displayed to the user
            - a challenge
            - a default result for the request
            - a place to store the actual result for the request
  
          The user_data argument is currently not set in the openAuth call.
          '''
          for credential in credentials:
              if credential[0] == libvirt.VIR_CRED_AUTHNAME:
                  credential[4] = username if username else \
                                  __salt__['config.get']('virt:connection:auth:username', credential[3])
              elif credential[0] == libvirt.VIR_CRED_NOECHOPROMPT:
                  credential[4] = password if password else \
                                  __salt__['config.get']('virt:connection:auth:password', credential[3])
              else:
                  log.info('Unhandled credential type: %s', credential[0])
          return 0