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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 _GetUncompressedStreamSize(self):
 """Retrieves the uncompressed stream size. Returns: int: uncompressed stream size. """

    self._file_object.seek(0, os.SEEK_SET)

    self._decompressor = self._GetDecompressor()
    self._uncompressed_data = b''

    compressed_data_offset = 0
    compressed_data_size = self._file_object.get_size()
    uncompressed_stream_size = 0

    while compressed_data_offset < compressed_data_size:
      read_count = self._ReadCompressedData(self._COMPRESSED_DATA_BUFFER_SIZE)
      if read_count == 0:
        break

      compressed_data_offset += read_count
      uncompressed_stream_size += self._uncompressed_data_size

    return uncompressed_stream_size