docs: def pure_nash_brute_gen(g, tol=None):
      """
      Generator version of `pure_nash_brute`.
  
      Parameters
      ----------
      g : NormalFormGame
      tol : scalar(float), optional(default=None)
          Tolerance level used in determining best responses. If None,
          default to the value of the `tol` attribute of `g`.
  
      Yields
      ------
      out : tuple(int)
          Tuple of Nash equilibrium pure actions.
  
      """
      for a in np.ndindex(*g.nums_actions):
          if g.is_nash(a, tol=tol):
              yield a