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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 pprint(self):
 """Print tag key=value pairs."""

        strings = []
        for key in sorted(self.keys()):
            values = self[key]
            for value in values:
                strings.append("%s=%s" % (key, value))
        return "\n".join(strings)