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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 hcompress(self, hashroot):
 """ Compress category 'hashroot', so hset is fast again hget will fail if fast_only is True for compressed items (that were hset before hcompress). """

        hfiles = self.keys(hashroot + "/*")
        all = {}
        for f in hfiles:
            # print "using",f
            all.update(self[f])
            self.uncache(f)

        self[hashroot + '/xx'] = all
        for f in hfiles:
            p = self.root / f
            if p.name == 'xx':
                continue
            p.unlink()