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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 setup_filter(self, root_path, path_list):

 """Setup proxy model filter parameters"""

        self.root_path = osp.normpath(to_text_string(root_path))
        self.path_list = [osp.normpath(to_text_string(p)) for p in path_list]
        self.invalidateFilter()