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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 _create_payload(self, symbols):
 """ Creates a payload with no none values. :param symbols: currency symbols to request specific exchange rates. :type symbols: list or tuple :return: a payload. :rtype: dict """

        payload = {'access_key': self.access_key}
        if symbols is not None:
            payload['symbols'] = ','.join(symbols)

        return payload