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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 shaped_metadata(self):
 """Return tifffile metadata from JSON descriptions as dicts."""

        if not self.is_shaped:
            return None
        return tuple(json_description_metadata(s.pages[0].is_shaped)
                     for s in self.series if s.kind.lower() == 'shaped')