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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 timezone(zone):
 """Try to get timezone using pytz or python-dateutil :param zone: timezone str :return: timezone tzinfo or None """

    try:
        import pytz
        return pytz.timezone(zone)
    except ImportError:
        pass
    try:
        from dateutil.tz import gettz
        return gettz(zone)
    except ImportError:
        return None