Getting this error when using tweepy – Twitter API

Python code used to gather tweets and send it to a csv file

keeps returning error

tweepy.error.RateLimitError: [{‘code’: 88, ‘message’: ‘Rate limit exceeded’}]

trying to get the most recent timeline and send all these tweets to the csv file

thanks for any help

def get_all_tweets(screen_name):

    #authorize twitter, initialize tweepy
    auth = tweepy.OAuthHandler(consumer_token, consumer_secret)
    auth.set_access_token(access_token, access_secret)
    api = tweepy.API(auth)

    #initialize a list to hold all the tweepy Tweets
    alltweets = []    


    new_tweets = api.home_timeline (screen_name = screen_name,count=20)

    #save most recent tweets
    alltweets.extend(new_tweets)

    #save the id of the oldest tweet less one
    oldest = alltweets[-1].id - 1

    while len(new_tweets) > 0:
        print ("getting tweets before %s" % (oldest))

        #all subsiquent requests use the max_id param to prevent duplicates
            new_tweets = api.home_timeline(screen_name =      screen_name,count=20,max_id=oldest)

        #save most recent tweets
        alltweets.extend(new_tweets)

        #update the id of the oldest tweet less one
        oldest = alltweets[-1].id - 1

        print ("...%s tweets downloaded so far" % (len(alltweets)))

    #transform the tweepy tweets into a 2D array that will populate the csv    
    outtweets = [[tweet.id_str, tweet.created_at, tweet.text.encode("utf-8")] for tweet in alltweets]

    #write the csv    
    with open('%s_tweetsBQ.csv' % screen_name, 'w') as f:
        writer = csv.writer(f)
        writer.writerow(["id","created_at","text"])
        writer.writerows(outtweets)

    pass


    if __name__ == '__main__':
    #pass in the username of the account you want to download
    get_all_tweets("BQ")