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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 addClassKey(self, klass, key, obj):
 """ Adds an object to the collection, based on klass and key. @param klass: The class of the object. @param key: The datastore key of the object. @param obj: The loaded instance from the datastore. """

        d = self._getClass(klass)

        d[key] = obj