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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 datetimeparse(s):
 """Parse a string date time to a datetime object. Suitable for dates serialized with .isoformat() :return: None, or an aware datetime instance, tz=UTC. """

    try:
        dt = dateutil.parser.parse(s)
    except ValueError:
        return None

    return utc_dt(dt)