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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 _get_association_classes(self, namespace):
 """ Return iterator of associator classes from the class repo Returns the classes that have associations qualifier. Does NOT copy so these are what is in repository. User functions MUST NOT modify these classes. Returns: Returns generator where each yield returns a single association class """


        class_repo = self._get_class_repo(namespace)
        # associator_classes = []
        for cl in six.itervalues(class_repo):
            if 'Association' in cl.qualifiers:
                yield cl
        return