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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 _get_master_address(self, instance):
 """ Get the master address from the instance configuration """


        master_address = instance.get(MASTER_ADDRESS)
        if master_address is None:
            master_address = instance.get(DEPRECATED_MASTER_ADDRESS)

            if master_address:
                self.log.warning(
                    'The use of `%s` is deprecated. Please use `%s` instead.'
                    % (DEPRECATED_MASTER_ADDRESS, MASTER_ADDRESS)
                )
            else:
                raise Exception('URL for `%s` must be specified in the instance configuration' % MASTER_ADDRESS)

        return master_address