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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 _hincrby(self, hashkey, attribute, command, type_, increment):
 """Shared hincrby and hincrbyfloat routine"""

        redis_hash = self._get_hash(hashkey, command, create=True)
        attribute = self._encode(attribute)
        previous_value = type_(redis_hash.get(attribute, '0'))
        redis_hash[attribute] = self._encode(previous_value + increment)
        return type_(redis_hash[attribute])