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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 _request_next_buffer(self):
 """Request next buffer. Requires self._offset and self._buffer are in consistent state. """

    self._buffer_future = None
    next_offset = self._offset + self._buffer.remaining()
    if next_offset != self._file_size:
      self._buffer_future = self._get_segment(next_offset,
                                              self._buffer_size)