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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 list_images(self):
 """ Return the list of available images for this node type :returns: Array of hash """


        try:
            return list_images(self._NODE_TYPE)
        except OSError as e:
            raise aiohttp.web.HTTPConflict(text="Can not list images {}".format(e))