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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_items(self):
 """ Return the item models associated with this Publish group. """

        from .layers import Layer

        # no expansion support, just URLs
        results = []
        for url in self.items:
            if '/layers/' in url:
                r = self._client.request('GET', url)
                results.append(self._client.get_manager(Layer).create_from_result(r.json()))
            else:
                raise NotImplementedError("No support for %s" % url)
        return results