text: """
  All types of notification
  :see Payload -> notification_type https://developers.facebook.com/docs/messenger-platform/send-api-reference
  """
  from __future__ import unicode_literals
  
  REGULAR = 'REGULAR'
  SILENT_PUSH = 'SILENT_PUSH'
  NO_PUSH = 'NO_PUSH'
  
  ALL_NOTIFICATION_TYPES = (
      REGULAR,
      SILENT_PUSH,
      NO_PUSH,
  )
  