Although the candidates are selected instead of elected, the process has to follow strict standards. 1. The candidates have to be always in the political system.
1 An example of mettle is a soldier's bravery.  An example of mettle is a person who has spirit and courage.
(music) A category of rock music encompassing a number of genres (including thrash metal, death metal, heavy metal, etc.) characterized by strong, fast drum-beats and distorted guitars. (archaic) The substance that constitutes something or someone; matter; hence, character or temper; mettle.