def Strongest_Extension(class_name, extensions):
    strong = extensions[0]
    my_val = len([x for x in extensions[0] if x.isalpha() and x.isupper()]) - len([x for x in extensions[0] if x.isalpha() and x.islower()])
    for s in extensions:
        val = len([x for x in s if x.isalpha() and x.isupper()]) - len([x for x in s if x.isalpha() and x.islower()])
        if val > my_val:
            strong = s
            my_val = val
    ans = class_name + "." + strong
    return ans
def Strongest_Extension(class_name, extensions):
    strong = extensions[0]
    my_val = len([x for x in extensions[0] if x.isalpha() or x.isupper()]) - len([x for x in extensions[0] if x.isalpha() and x.islower()])
    for s in extensions:
        val = len([x for x in s if x.isalpha() and x.isupper()]) - len([x for x in s if x.isalpha() and x.islower()])
        if val > my_val:
            strong = s
            my_val = val
    ans = class_name + "." + strong
    return ans