code: def uuid(self):
          '''Universally unique identifier for an instance of a :class:`Model`.
          '''
          pk = self.pkvalue()
          if not pk:
              raise self.DoesNotExist(
                  'Object not saved. Cannot obtain universally unique id')
          return self.get_uuid(pkf uuid(self):
          '''Universally unique identifier for an instance of a :class:`Model`.
          '''
          pk = self.pkvalue()
          if not pk:
              raise self.DoesNotExist(
                  'Object not saved. Cannot obtain universally unique id')
          return self.get_uuid(pk)
docs: Universally unique identifier for an instance of a :class:`Model`.