Twitter Streaming APIで取得した内容をJSON形式で書き出す

# -*- coding:utf-8 -*-

from requests_oauthlib import OAuth1Session
import json, datetime, time, sys

KEYS = { # 自分のアカウントで入手したキーを下記に記載
    'consumer_key':'*******',
    'consumer_secret':'*******',
    'access_token':'*******',
    'access_secret':'*******'
   }

# Twitter APIへの接続
twitter = OAuth1Session(KEYS['consumer_key'],KEYS['consumer_secret'],
                        KEYS['access_token'],KEYS['access_secret'])

nRstTm = 15 # Rate Limited待機時間
stKeyWrd = 'twitter' # 検索ワード

url = 'https://stream.twitter.com/1.1/statuses/filter.json'

# ツイートのdatetimeを日本標準時間に変換
def str_to_datetime_jp(datetimes):
    dts = datetime.datetime.strptime(datetimes,'%a %b %d %H:%M:%S +0000 %Y')
    return(dts+ datetime.timedelta(hours=9)).strftime("%Y-%m-%d %H:%M:%S")

f = open("teststream.json", "w",encoding='utf-8')
while(True): 
    try:
        req = twitter.post(url,
                    data= {"track":stKeyWrd},
                    stream = True)

        if req.status_code == 200: 
            for line in req.iter_lines():
                work = json.loads(line.decode('utf-8'))
                workuser = work['user']
                tweet_json = {"tweetId":workuser["id"],
                              "name":workuser["name"],
                              "screen_name":workuser["screen_name"],
                              "text":work["text"],
                              "created_at":str_to_datetime_jp(work["created_at"])
                              } 
                print('write')
                json.dump(tweet_json, f, ensure_ascii=False, indent=2,sort_keys=True)

        # 短時間でアクセスしすぎたら420エラーになるので待機
        elif req.status_code == 420:
            print('Rate Limited：',nRstTm,'分待機')
            time.sleep(nRstTm)
        else:
            # とりあえず処理抜けとく
            print('req.status_code',req.status_code)
            break

    # streamで取得できない場合、以下例外になるので再度取得しなおし
    except json.JSONDecodeError as e:
        print('再取得')
        pass
    except KeyboardInterrupt:
        print('処理終了')
        f.close()
        break
    except:
        print('except', sys.exc_info())
        pass

            for line in req.iter_lines():
                work = json.loads(line.decode('utf-8'))

    except json.JSONDecodeError as e:
        print('再取得')
        pass