Query the server to delete the key specified from the cache
        specified.

        Keyword arguments:
        key -- the key the item is stored under. Required.
        cache -- the cache to delete the item from. Defaults to None, which
                 uses self.name. If no name is set, raises a ValueError.

def delete(self, key, cache=None):
        """Query the server to delete the key specified from the cache
        specified.

        Keyword arguments:
        key -- the key the item is stored under. Required.
        cache -- the cache to delete the item from. Defaults to None, which
                 uses self.name. If no name is set, raises a ValueError.
        """
        if cache is None:
            cache = self.name
        if cache is None:
            raise ValueError("Cache name must be set")
        cache = quote_plus(cache)
        key = quote_plus(key)

        self.client.delete("caches/%s/items/%s" % (cache, key))

        return True