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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 download(self, filename, output, packethook=None, timeout=SOCK_TIMEOUT):
 """This method initiates a tftp download from the configured remote host, requesting the filename passed. It writes the file to output, which can be a file-like object or a path to a local file. If a packethook is provided, it must be a function that takes a single parameter, which will be a copy of each DAT packet received in the form of a TftpPacketDAT object. The timeout parameter may be used to override the default SOCK_TIMEOUT setting, which is the amount of time that the client will wait for a receive packet to arrive. Note: If output is a hyphen, stdout is used."""

        # We're downloading.
        log.debug("Creating download context with the following params:")
        log.debug("host = %s, port = %s, filename = %s" % (self.host, self.iport, filename))
        log.debug("options = %s, packethook = %s, timeout = %s" % (self.options, packethook, timeout))
        self.context = TftpContextClientDownload(self.host,
                                                 self.iport,
                                                 filename,
                                                 output,
                                                 self.options,
                                                 packethook,
                                                 timeout,
                                                 localip = self.localip)
        self.context.start()
        # Download happens here
        self.context.end()

        metrics = self.context.metrics

        log.info('')
        log.info("Download complete.")
        if metrics.duration == 0:
            log.info("Duration too short, rate undetermined")
        else:
            log.info("Downloaded %.2f bytes in %.2f seconds" % (metrics.bytes, metrics.duration))
            log.info("Average rate: %.2f kbps" % metrics.kbps)
        log.info("%.2f bytes in resent data" % metrics.resent_bytes)
        log.info("Received %d duplicate packets" % metrics.dupcount)