random
import random print(random.random()) #(0,1)----float 大于0且小于1之间的小数 print(random.randint(1, 3)) # [1,3] 大于等于1且小于等于3之间的整数 print(random.randrange(1, 3)) # [1,3) 大于等于1且小于3之间的整数 print(random.choice([111, 'aaa', [4, 5]])) # 1或者23或者[4,5] print(random.sample([111, 'aaa', 'ccc','ddd'],2)) # 列表元素任意2个组合 print(random.uniform(1, 3)) # 大于1小于3的小数,如1.927109612082716 item = [1, 3, 5, 7, 9] random.shuffle(item) # 打乱item的顺序,相当于"洗牌" print(item)
# 应用:随机验证码 import random def make_code(size=4): res='' for i in range(size): s1=chr(random.randint(65,90)) s2=str(random.randint(0,9)) res+=random.choice([s1,s2]) return res print(make_code(6))
os
# 获取某一个文件夹下所有的子文件以及子文件夹的名字 res=os.listdir('.') print(res)
os.remove("newname") 删除一个文件
os.rename("oldname","newname") 重命名文件/目录
os.environ()# 规定:key与value必须都为字符串 os.environ['aaaaaaaaaa']='111' print(os.environ)
print(os.path.dirname(r'/a/b/c/d.txt')) print(os.path.basename(r'/a/b/c/d.txt')) print(os.path.isfile(r'笔记.txt')) print(os.path.isfile(r'aaa')) print(os.path.isdir(r'aaa')) print(os.path.join('a','/','b','c','d'))
sys
import time def progress(percent): if percent > 1: percent = 1 res = int(50 * percent) * '#' print('\r[%-50s] %d%%' % (res, int(100 * percent)), end='') recv_size = 0 total_size = 1025011 while recv_size < total_size: time.sleep(0.01) recv_size += 1024 # 打印进度条 # print(recv_size) percent = recv_size / total_size progress(percent)