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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 journal_event(events):
 """Group multiple events into a single one."""

    reasons = set(chain.from_iterable(e.reasons for e in events))
    attributes = set(chain.from_iterable(e.file_attributes for e in events))

    return JrnlEvent(events[0].file_reference_number,
                     events[0].parent_file_reference_number,
                     events[0].file_name,
                     events[0].timestamp,
                     list(reasons), list(attributes))