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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 format_datetime(time):
 """ Formats a date, converting the time to the user timezone if one is specified """

    user_time_zone = timezone.get_current_timezone()
    if time.tzinfo is None:
        time = time.replace(tzinfo=pytz.utc)
        user_time_zone = pytz.timezone(getattr(settings, 'USER_TIME_ZONE', 'GMT'))

    time = time.astimezone(user_time_zone)
    return time.strftime("%b %d, %Y %H:%M")