网络爬虫（OD两点间的行车距离和行车时间）

import pandas as pd
import json
import threading
import requests
import time
import csv
from threading import Thread
keys=['21ea35170b930fcc916ccd16c8acfd1f','38b03445dd89225d0bae29832ce10170']
threadmax1 = threading.BoundedSemaphore(90)#总线程数
threadmax2 = threading.BoundedSemaphore(90)#总线程数
mu = threading.Lock()#线程锁
def write_file(data):
    filename='result_car1.csv'
    mu.acquire(True)
    with open(filename,'a',newline='')as csvf:
        writer=csv.writer(csvf)
        head=['编号','O经度','O纬度','D经度','D纬度','行驶距离','行驶时间','状态']
        fieldnames=['bh','O_lon','O_lat','D_lon','D_lat','distance','duration','state']
        write=csv.DictWriter(csvf,fieldnames=fieldnames)
        with open(filename,'r',newline='') as csvreader:
                reade