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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 _needs_region_update(out_file, samples):
 """Check if we need to update BED file of regions, supporting back compatibility. """

    nblock_files = [x["regions"]["nblock"] for x in samples if "regions" in x]
    # For older approaches and do not create a new set of analysis
    # regions, since the new algorithm will re-do all BAM and variant
    # steps with new regions
    for nblock_file in nblock_files:
        test_old = nblock_file.replace("-nblocks", "-analysisblocks")
        if os.path.exists(test_old):
            return False
    # Check if any of the local files have changed so we need to refresh
    for noblock_file in nblock_files:
        if not utils.file_uptodate(out_file, noblock_file):
            return True
    return False