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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 bind_address(self):
 """The bind address the iperf3 instance will listen on use * to listen on all available IPs :rtype: string """

        result = c_char_p(
            self.lib.iperf_get_test_bind_address(self._test)
        ).value
        if result:
            self._bind_address = result.decode('utf-8')
        else:
            self._bind_address = '*'

        return self._bind_address