'Gets stream buffer since the last GetValueAndReset() call.'

def GetValueAndReset(self):

    if (not self._stream):
        raise ArchiveAlreadyClosedError('Attempting    to    get    a    value    from    a    closed    stream.')
    value = self._stream.getvalue()
    self._stream.seek(0)
    self._stream.truncate()
    return value
