class counter:
    def __init__(self,fn):
        self.count=0
        self.fn=fn
        
    def __call__(self,*args):
        self.count=self.count+1
        return self.fn(*args)
        
    def counter(self):
        return self.count
        
@counter
def fun(a, b):
    return a * 1 + b

print(fun.counter())
res = sum(fun(i, i + 1) for i in range(5))
print(fun.counter(), res)