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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 hash(self):
 """Hashes of a hierarchy child changes if the parent changes"""

        # Do not apply filters here (speed)
        hph = self.hparent.hash
        hpfilt = hashobj(self.hparent._filter)
        dhash = hashobj(hph + hpfilt)
        return dhash