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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 set_option(self, key, value):
 """Sets a option for this session. For a detailed list of available options see the librtmp(3) man page. :param key: str, A valid option key. :param value: A value, anything that can be converted to str is valid. Raises :exc:`ValueError` if a invalid option is specified. """


        akey = AVal(key)
        aval = AVal(value)

        res = librtmp.RTMP_SetOpt(self.rtmp, akey.aval, aval.aval)

        if res < 1:
            raise ValueError("Unable to set option {0}".format(key))

        self._options[akey] = aval