python之with上下文管理

#文件对象又称为文件句柄

with open('a.txt',mode = 'rt') as f1,\
	open('b.txt',mode='rt') as f2:
	res1 = f1.read()
	res2 = f2.read()
	print(res1)
	print(res2)

	f1.close()
	f2.close()