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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 _region(decoder, timeout):
 """A context manager for `DmtxRegion`, created and destroyed by `dmtxRegionFindNext` and `dmtxRegionDestroy`. Args: decoder (POINTER(DmtxDecode)):
 timeout (int or None):
 Yields: DmtxRegion: The next region or None, if all regions have been found. """

    region = dmtxRegionFindNext(decoder, timeout)
    try:
        yield region
    finally:
        if region:
            dmtxRegionDestroy(byref(region))