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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 joinOnAs(self, model, onIndex, whatAs):
 """ Like `joinOn` but allows setting the joined results name to access it from. Performs an eqJoin on with the given model. The resulting join will be accessible through the given name. """

        return self._joinOnAsPriv(model, onIndex, whatAs)