Minor formatting

Author: gaffney2010

axelrod/strategies/axelrod_second.py

@@ -1453,4 +1453,4 @@ def strategy(self, opponent: Player) -> Action:
         self.flack += 1 if opponent.history[-1] == D else 0
         self.flack *= 0.5  # Defections have half-life of one round
 
-        return random_choice(1.0-self.flack)
+        return random_choice(1.0 - self.flack)