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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 clean(self):
 """Clear the data. For each ``YTStor`` object present in this object ``clean`` method is executed."""


        for s in self.visible_files.values():
            s.clean()
        for s in [sub[1][x] for sub in self.avail_files.values() for x in sub[1]]: # Double list comprehensions aren't very
            s.clean()