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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 to_id(self):
 """ Convert TraceId object to a string. """

        return "%s%s%s%s%s" % (TraceId.VERSION, TraceId.DELIMITER,
                               format(self.start_time, 'x'),
                               TraceId.DELIMITER, self.__number)