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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 add_index_boost(self, index, boost):
 """Add a boost on an index. The Search object will be returned, so calls to this can be chained. """

        if boost is None:
            if index in self.index_boost:
                del(self.index_boost[index])
        else:
            self.index_boost[index] = boost
        return self