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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):
 """ Get the stream from HTTP """

        _, ext = os.path.splitext(self.url)
        if ext == ".mp3":
            self.output_extention = "mp3"
        else:
            self.output_extention = "mp4"  # this might be wrong..
        data = self.http.request("get", self.url, stream=True)
        try:
            total_size = data.headers['content-length']
        except KeyError:
            total_size = 0
        total_size = int(total_size)
        bytes_so_far = 0

        file_d = output(self.output, self.config, self.output_extention)
        if file_d is None:
            return

        eta = ETA(total_size)
        for i in data.iter_content(8192):
            bytes_so_far += len(i)
            file_d.write(i)
            if not self.config.get("silent"):
                eta.update(bytes_so_far)
                progressbar(total_size, bytes_so_far, ''.join(["ETA: ", str(eta)]))

        file_d.close()
        self.finished = True