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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_by_pattern(self, pattern, filter_type=DefaultFilterType):
 """ Add a files filter by linux-style pattern to this iterator. :param pattern: linux-style files pattern (or list of patterns) """

        self.add_filter(FilterPattern(pattern), filter_type)
        return self