docs: def reverse(func):
      """Given a function f(a, b), returns f(b, a)"""
      @wraps(func)
      def reversed_func(a, b):
          return func(b, a)
      reversed_func.__doc__ = "Reversed argument form of %s" % func.__doc__
      reversed_func.__name__ = "reversed %s" % func.__name__
      return reversed_func