@_handle_container_not_found
    def set_metadata(self, container, metadata, clear=False, prefix=None):
        # Add the metadata prefix, if needed.
        if prefix is None:
            prefix = CONTAINER_META_PREFIX
        massaged = _massage_metakeys(metadata, prefix)
        new_meta = {}
        if clear:
            curr_meta = self.api.get_container_metadata(container,
                    prefix=prefix)
            for ckey in curr_meta:
                new_meta[ckey] = ""
        utils.case_insensitive_update(new_meta, massaged)
        name = utils.get_name(container)
        uri = "/%s" % name
        resp, resp_body = self.api.method_post(uri, headers=new_meta)
        return 200 <= resp.status_code <= 299
Accepts a dictionary of metadata key/value pairs and updates the
dataset/ETHPy150Open rackspace/pyrax/pyrax/object_storage.py/ContainerManager.set_metadata