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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 sendDAT(self):
 """This method sends the next DAT packet based on the data in the context. It returns a boolean indicating whether the transfer is finished."""

        finished = False
        blocknumber = self.context.next_block
        # Test hook
        if DELAY_BLOCK and DELAY_BLOCK == blocknumber:
            import time
            log.debug("Deliberately delaying 10 seconds...")
            time.sleep(10)
        dat = None
        blksize = self.context.getBlocksize()
        buffer = self.context.fileobj.read(blksize)
        log.debug("Read %d bytes into buffer", len(buffer))
        if len(buffer) < blksize:
            log.info("Reached EOF on file %s"
                % self.context.file_to_transfer)
            finished = True
        dat = TftpPacketDAT()
        dat.data = buffer
        dat.blocknumber = blocknumber
        self.context.metrics.bytes += len(dat.data)
        log.debug("Sending DAT packet %d", dat.blocknumber)
        self.context.sock.sendto(dat.encode().buffer,
                                 (self.context.host, self.context.tidport))
        if self.context.packethook:
            self.context.packethook(dat)
        self.context.last_pkt = dat
        return finished