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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 parse_journal(journal):
 """Parses the USN Journal content removing duplicates and corrupted records. """

    events = [e for e in journal if not isinstance(e, CorruptedUsnRecord)]
    keyfunc = lambda e: str(e.file_reference_number) + e.file_name + e.timestamp
    event_groups = (tuple(g) for k, g in groupby(events, key=keyfunc))

    if len(events) < len(list(journal)):
        LOGGER.debug(
            "Corrupted records in UsnJrnl, some events might be missing.")

    return [journal_event(g) for g in event_groups]