qq_40492771的博客

m = [‘W’]添加appendm.append(‘L’)m[‘W’, ‘L’]extendm.extend([‘O’,‘P’])m[‘W’,‘L’,‘O’,‘P’]insertm.insert(2,‘A’)m[‘W’,‘L’,‘A’,‘O’,‘P’]m[2,4][‘A’,‘O’]m[2:][‘O’,‘P’]m[:4][‘W’,‘L’,‘A’,‘O’]m[...

python数据类型整形 2布尔类型 True False浮点型 1.2e记法 1e10 2e-10字符串 “lin”python类型转化int()n=int(5.6) n=5 除去小数，取整（砍掉小数）n=int(‘520’) n=520n=int(“lin”) 报错float()n= float(520) n=520.0str()n=str(2) ...

import randomdef code(n): mycode = '' for i in range(n): str1 = chr(random.randint(97,122)) str2 = chr(random.randint(65,90)) str3 = str(random.randint(0,10)) ...

数据类型的常用操作和内置方法整型,浮点型:加减乘除...bool类型:notstr:1\ 按索引取值 str[索引]2 切片 str[起始索引:终止索引:步长] 顾头不顾尾 str[起始索引:] 默认取到最后一个 str[:终止索引] 默认从第一个开始取 str[:] 第一个到最后一个3 遍历 for i in str4 +...

import picklelist = [1,2,3,4]f = open(“list.pkl”,‘wb’)pickle.dump(list,f)pickle.close()f.close()f = open(“list.pkl”,“rb”)list2 = pickle.load(f)print(list2)[1, 2, 3, 4]

capitalizem = ‘lin’m.capitalize()m=‘Lin’casefoldm=‘LIN’m.casefold()m=‘lin’centerm=‘lin’m.center(3)m=’ lin ’countm=‘linlinlinlin’m.count(‘l’) 4m.count(‘l’,3) 3m.count(‘l’,3,8) ...

首先安装pymysql 模块，可以通过 pip 安装在进行mysql操作前，先设置MySQL服务器地址，MySQL服务器端口号，用户名，密码，数据库名称。import pymysqlDBHOST = 'localhost'DBUSER = 'root'DBPASS = 'root'DBNAME = 'datest'建立连接try: db = pymysql.connect(DBHOST,DBUSER,DBPASS,DBNAME) print('OK')except py