def has_improvement(gain_a, gain_b):
    """Returns True if gain_a has at least 1 improvement in any parameter
    compared to gain_b."""
    return (gain_a.firepower > gain_b.firepower or
            gain_a.thunderstroke > gain_b.thunderstroke or
            gain_a.anti_air > gain_b.anti_air or
            gain_a.armor > gain_b.armor)