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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 check_user(self, todays_facts):
 """check if we need to notify user perhaps"""

        interval = self.conf_notify_interval
        if interval <= 0 or interval >= 121:
            return

        now = dt.datetime.now()
        message = None

        last_activity = todays_facts[-1] if todays_facts else None

        # update duration of current task
        if last_activity and not last_activity['end_time']:
            delta = now - last_activity['start_time']
            duration = delta.seconds /  60

            if duration and duration % interval == 0:
                message = _("Working on %s") % last_activity['name']
                self.notify_user(message)

        elif self.conf_notify_on_idle:
            #if we have no last activity, let's just calculate duration from 00:00
            if (now.minute + now.hour * 60) % interval == 0:
                self.notify_user(_("No activity"))