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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 show_activity_count(date=None):
 """ Simple filter to get activity count for a given day. Defaults to today. """

    if not date:
        today = datetime.datetime.now() - datetime.timedelta(hours = 24)
        return Activity.objects.filter(timestamp__gte=today).count()
    return Activity.objects.filter(timestamp__gte=date).count()