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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 _call_zincrby(self, command, value, *args, **kwargs):
 """ This command update a score of a given value. But it can be a new value of the sorted set, so we index it. """

        if self.indexable:
            self.index([value])
        return self._traverse_command(command, value, *args, **kwargs)