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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 write_oggopus_output_gain(file, new_output_gain):
 """ Write output gain Opus header for a file. file must be an object successfully used by parse_oggopus_output_gain. """

  opus_header_pos = file.tell()

  # write Opus header with new gain
  file.seek(opus_header_pos + OGG_OPUS_ID_HEADER_GAIN_OFFSET)
  file.write(OGG_OPUS_ID_HEADER_GAIN.pack(new_output_gain))

  # compute page crc
  file.seek(0)
  page = file.read(opus_header_pos + OGG_OPUS_ID_HEADER.size)
  computed_crc = _compute_ogg_page_crc(page)

  # write CRC
  file.seek(OGG_FIRST_PAGE_HEADER_CRC_OFFSET)
  file.write(OGG_FIRST_PAGE_HEADER_CRC.pack(computed_crc))