Python: What is the class-based decorator with state?

1import functools
2import time
3
4class RateLimiter:
5    def __init__(self, max_calls, period):
6        self.max_calls = max_calls
7        self.period = period
8        self.calls = []
9
10    def __call__(self, func):
11        @functools.wraps(func)
12        def wrapper(*args, **kwargs):
13            now = time.time()
14            # Remove old calls
15            self.calls = [t for t in self.calls if now - t < self.period]
16
17            if len(self.calls) >= self.max_calls:
18                raise Exception("Rate limit exceeded")
19
20            self.calls.append(now)
21            return func(*args, **kwargs)
22
23        wrapper.reset = self.reset
24        return wrapper
25
26    def reset(self):
27        self.calls.clear()
28
29@RateLimiter(max_calls=5, period=60)
30def api_call():
31    return "Response"
32
33# Works
34for _ in range(5):
35    api_call()  # OK
36
37# api_call()  # Exception: Rate limit exceeded
38api_call.reset()  # Reset counter
39api_call()  # OK again