The Most Wanted Letter Misson Error
Sorry for my English. My code:
def checkio(a): b = a.lower() d = {i : b.count(i) for i in b.lower() if i.isalpha()} m = max(d, key=d.get) return min(d) if m == 1 else m
I tried on Output (Python console), and the result is exactly. But when I run the test, It's wrong.