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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 delete(self):
 """ When the instance is deleted, we propagate the deletion to the related collections, which will remove it from the related fields. """

        for related_collection_name in self.related_collections:
            related_collection = getattr(self, related_collection_name)
            related_collection.remove_instance()
        return super(RelatedModel, self).delete()