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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 access_level_up_to(self, access_level):
 """ returns all items that have an access level equal or lower than the one specified """

        # if access_level is number
        if isinstance(access_level, int):
            value = access_level
        # else if is string get the numeric value
        else:
            value = ACCESS_LEVELS.get(access_level)
        # return queryset
        return self.filter(access_level__lte=value)