How to implement rate limiting in Python

import time
import random

class RateLimiter:
    def __init__(self, max_calls, per_seconds):
        self.max_calls = max_calls
        self.per_seconds = per_seconds
        self.timestamps = []
    
    def allow(self):
        now = time.time()
        self.timestamps = [t for t in self.timestamps if now - t < self.per_seconds]
        if len(self.timestamps) < self.max_calls:
            self.timestamps.append(now)
            return True
        return False

def parse_data_with_retry(lines, limiter, max_attempts=5):
    parsed = []
    for line in lines:
        attempts = 0
        while attempts < max_attempts:
            if not limiter.allow():
                time.sleep(0.1)
                attempts += 1
                continue
            try:
                parsed.append(float(line.strip()))
                break
            except ValueError:
                parsed.append(None)
                break
    return parsed

if __name__ == "__main__":
    random.seed(42)
    raw_data = [random.randint(0, 100) for _ in range(10)]
    data_lines = [str(x) for x in raw_data] + ["not_a_number"]
    limiter = RateLimiter(max_calls=3, per_seconds=1)
    result = parse_data_with_retry(data_lines, limiter)
    print("Parsed data:", result)