code: def get_referenced_object(self):
          
  
          if self._UserLight is not None:
              return self._UserLight
  
          if self._UserPerson is not None:
              return self._UserPerson
  
          if self._UserCompany is not None:
              return self._UserCompany
  
          if self._UserApiKey is not None:
              return self._UserApiKey
  
          raise exception.BunqException(self._ERROR_NULL_FIELDS)
docs: :rtype: core.BunqModel
          :raise: BunqException