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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 getAllAnnotationSets(self):
 """ Returns all variant annotation sets on the server. """

        for variantSet in self.getAllVariantSets():
            iterator = self._client.search_variant_annotation_sets(
                variant_set_id=variantSet.id)
            for variantAnnotationSet in iterator:
                yield variantAnnotationSet