def tag(self):
        """
        Get the string representation of the tag used to annotate the status in VOSpace.
        @return: str
        """
        return "{}{}_{}{:02d}".format(self.target.prefix,
                                      self,
                                      self.target.version,
                                      self.target.ccd)
Get the string representation of the tag used to annotate the status in VOSpace.
        @return: str