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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 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)