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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 get_id(self, grp):
 """ Return a hash of the tuple of indices that specify the group """

        thehash = hex(hash(grp))
        if ISPY3:  # use default encoding to get bytes
            thehash = thehash.encode()
        return self.cache.get(grp, hashlib.sha1(thehash).hexdigest())