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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 server_hostname(self):
 """The server hostname to connect to. Accepts DNS entries or IP addresses. :rtype: string """

        result = c_char_p(
            self.lib.iperf_get_test_server_hostname(self._test)
        ).value
        if result:
            self._server_hostname = result.decode('utf-8')
        else:
            self._server_hostname = None
        return self._server_hostname