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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_images(self):
 """Get available images. We cache the results in order to reduce network usage. """

        self._init_os_api()
        try:
            # python-novaclient < 8.0.0
            return self.nova_client.images.list()
        except AttributeError:
            # ``glance_client.images.list()`` returns a generator, but callers
            # of `._get_images()` expect a Python list
            return list(self.glance_client.images.list())