text: import mongoengine
  
  
  class AccessToken(mongoengine.Document):
      user_id = mongoengine.IntField()
      client_id = mongoengine.IntField()
      access_token = mongoengine.StringField()
      refresh_token = mongoengine.StringField()
      scope = mongoengine.ListField(mongoengine.StringField())
      expire = mongoengine.DateTimeField()
  
      meta = {
          'indexes': ['access_token', 'expire'],
      }