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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 match_blocks(hash_func, old_children, new_children):
 """Use difflib to find matching blocks."""

    sm = difflib.SequenceMatcher(
        _is_junk,
        a=[hash_func(c) for c in old_children],
        b=[hash_func(c) for c in new_children],
    )
    return sm