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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(cls, id):
        ''' Retrieves an object by id. Returns None in case of failure '''

        if not id:
            return None

        redis = cls.get_redis()
        key = '{}:{}:obj'.format(cls.cls_key(), id)

        if not redis.exists(key):
            return None

        obj = cls(id=id)
        obj._persisted = True

        data = debyte_hash(redis.hgetall(key))

        for fieldname, field in obj.proxy:
            value = field.recover(data, redis)

            setattr(
                obj,
                fieldname,
                value
            )

        return obj