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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 determine_types(self):
 """ Determine ES type names from request data. In particular `request.matchdict['collections']` is used to determine types names. Its value is comma-separated sequence of collection names under which views have been registered. """

        from nefertari.elasticsearch import ES
        collections = self.get_collections()
        resources = self.get_resources(collections)
        models = set([res.view.Model for res in resources])
        es_models = [mdl for mdl in models if mdl
                     and getattr(mdl, '_index_enabled', False)]
        types = [ES.src2type(mdl.__name__) for mdl in es_models]
        return types