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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_deferred_transfer(self, enable):
 """ Allow transfers to be delayed and buffered By default deferred transfers are turned off. All reads and writes will be completed by the time the function returns. When enabled packets are buffered and sent all at once, which increases speed. When memory is written to, the transfer might take place immediately, or might take place on a future memory write. This means that an invalid write could cause an exception to occur on a later, unrelated write. To guarantee that previous writes are complete call the flush() function. The behaviour of read operations is determined by the modes READ_START, READ_NOW and READ_END. The option READ_NOW is the default and will cause the read to flush all previous writes, and read the data immediately. To improve performance, multiple reads can be made using READ_START and finished later with READ_NOW. This allows the reads to be buffered and sent at once. Note - All READ_ENDs must be called before a call using READ_NOW can be made. """

        if self._deferred_transfer and not enable:
            self.flush()
        self._deferred_transfer = enable