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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 add_filter(self, filter_values):
 """ Construct a filter. """

        if not filter_values:
            return

        f = self.get_value_filter(filter_values[0])
        for v in filter_values[1:]:
            f |= self.get_value_filter(v)
        return f