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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 get_thumbnail_paths(self):
 """ Helper function used to avoid processing thumbnail files during `os.walk`. """

        thumbnail_path_tuples = []
        # channel thumbnail
        channel_info = self.get_channel_info()
        chthumbnail_path = channel_info.get('thumbnail_chan_path', None)
        if chthumbnail_path:
            chthumbnail_path_tuple = path_to_tuple(chthumbnail_path, windows=self.winpaths)
            thumbnail_path_tuples.append(chthumbnail_path_tuple)
        # content thumbnails
        for content_file_path_tuple, row in self.contentcache.items():
            thumbnail_path = row.get('thumbnail_chan_path', None)
            if thumbnail_path:
                thumbnail_path_tuple = path_to_tuple(thumbnail_path, windows=self.winpaths)
                thumbnail_path_tuples.append(thumbnail_path_tuple)
        return thumbnail_path_tuples