import time
from datetime import datetime, timedelta

class TwitterRateLimiter:
    def __init__(self, max_calls, period):
        self.max_calls = max_calls
        self.period = timedelta(seconds=period)
        self.calls = []
    
    def wait_if_needed(self):
        now = datetime.now()
        # 移除过期的调用记录
        self.calls = [call for call in self.calls if now - call < self.period]
        
        if len(self.calls) >= self.max_calls:
            oldest_call = self.calls[0]
            wait_time = (oldest_call + self.period - now).total_seconds()
            if wait_time > 0:
                time.sleep(wait_time)
        
        self.calls.append(datetime.now())

import random
import time

def call_twitter_api_with_retry(api_call_func, max_retries=5):
    retry_count = 0
    while retry_count < max_retries:
        try:
            return api_call_func()
        except RateLimitError as e:
            wait_time = min((2 ** retry_count) + random.random(), 60)  # 指数退避加随机抖动
            time.sleep(wait_time)
            retry_count += 1
    raise Exception("Max retries exceeded")

from google.appengine.api import memcache

def get_twitter_data(user_id):
    cache_key = f"twitter_{user_id}"
    data = memcache.get(cache_key)
    if data is None:
        data = twitter_api.get_user_data(user_id)  # 实际API调用
        memcache.add(cache_key, data, 300)  # 缓存5分钟
    return data