Python多线程如何同时处理多个文件

import cv2
def func(video_names):
    for video_name in video_names:
        cap = cv2.VideoCapture(video_name)
        while True:
            ret, frame = cap.read()
            if ret:
                # process temp frame
            else:
                break

import threading
# video_names_list = [part_names_1_list, part_names_2_list, ..., part_names_k_list]
for part_video in video_names_list:
    thread = threading.Thread(target=func, args=([part_video]))
    thread.start()

import os
import threading  #导入进程
import csv
import time
from Mongo_cache import MongoCache 
import win32com.client
import winsound
NUM_THREAD = 5
COUNT = 0
lock = threading.Lock()
cache = MongoCache()     #数据库连接初始化
def worker():
"""
func： 从csv文件中读取数据，并将数据返回
"""
    for path in os.listdir(os.getcwd()):
        #print("当前工作目录", path)
        file_name = path.split('.')
        #print(file_name)
        if file_name[-1] == 'csv':
            #print("地址是:",path)
            file = open(path)
            data = csv.reader(file)
            return data
        else:
            pass
def save_info(data,i, num_retries=2):
"""
func： 将数据保存
"""
    global COUNT
    global lock
    global cache
    for _, website in data:
        try:
            lock.acquire()
            #print("线程{}》》》{}正在运行".format(threading.current_thread().name, i))
            item = {'website':website}
            cache(item)
            COUNT += 1
        except:
            if num_retries > 0:
                save_info(data, i, num_retries-1)
        finally:
            lock.release()
def main():
"""
启动线程
"""
    print("start working")
    print("working...")
    data = worker()
    threads = []   #设置主线程
    for i in range(NUM_THREAD):
        t = threading.Thread(target=save_info, args=(data, i))
        threads.append(t)
    for i in range(NUM_THREAD):
        threads[i].start()
    for i in range(NUM_THREAD):
        threads[i].join()
    print("all was done!")
if __name__ == '__main__':
    s_time = time.time()
    main()
    e_time = time.time()
    print("总的信息条数：", COUNT)
    print("总耗时：", e_time-s_time)
    speak = win32com.client.Dispatch('SAPI.SPVOICE')
    speak.Speak("早上好，eric，程序结束！")

import pickle
import zlib
from bson.binary import Binary 
from datetime import datetime, timedelta
from pymongo import MongoClient
import time
class MongoCache(object):
    def __init__(self, client=None, expires=timedelta(days=30)):
        self.client = MongoClient('localhost', 27017) if client is None else client
        self.db = self.client.cache
        #self.db.webpage.create_index('timestamp', expireAfterSeconds=expires.total_seconds())  #设置自动删除时间
    def __call__(self,url):
        self.db.webpage.insert(url)
        #print("保存成功")
    def __contains__(self,url):
        try:
            self[url]
        except KeyError:
            return False
        else:
            return True
    def __getitem__(self, url):
        record = self.db.webpage.find_one({'_id':url})
        if record:
            return pickle.loads(zlib.decompress(record['result']))
        else:
            raise KeyError(url + 'dose not exist')
    def __setitem__(self, url, result):
        record = {'result': Binary(zlib.compress(pickle.dumps(result))), 'timestamp':datetime.utcnow()}
        self.db.webpage.update({'_id':url},{'$set':record},upsert=True)
    def clear(self):
        self.db.webpage.drop()

start working
working...
all was done!
总的信息条数： 1000000
总耗时： 427.4034459590912