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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 deleteMediaPreviews(self):
 """ Delete the preview thumbnails for items in this library. This cannot be undone. Recreating media preview files can take hours or even days. """

        key = '/library/sections/%s/indexes' % self.key
        self._server.query(key, method=self._server._session.delete)