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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 relative(self):
 """Return a relative part of the URL. scheme, user, password, host and port are removed. """

        if not self.is_absolute():
            raise ValueError("URL should be absolute")
        val = self._val._replace(scheme="", netloc="")
        return URL(val, encoded=True)