# 写方法1

 f  = open('tmp.txt','w')

 f.write('hello world')

 f.close()

 # 写方法2

 with open('tmp.txt','w') as f:

     f.write('hello \n word')

 # 读

 with open('tmp.txt', 'r') as f:

     print(f.read())

 # 逐行读

 with open('tmp.txt','r') as f:

     for line in f.readlines():

         print(line.strip())#strip()去除空行