import random
def get_user_agent():
    user_agent_list=[
        "Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/535.1 (KHTML, like Gecko) Chrome/14.0.835.163 Safari/535.1",
        "Mozilla/5.0 (Windows NT 6.1; WOW64; rv:6.0) Gecko/20100101 Firefox/6.0",
        "Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.157 Safari/537.36",
        "Opera/9.80 (Windows NT 6.1; U; zh-cn) Presto/2.9.168 Version/11.50"
    ]
    random_int=random.randint(0, len(user_agent_list)-1)
    return  user_agent_list[random_int]
