自学python练习题

1.输入一个文件名，检测是否存在，如果不存在创建文件并写入内容：

import os
while True:
	filename=input('Please enter the filename')
	if os.path.exists(filename):
		print('the file is exist')
		break
	else:
		all=[]
		while True:
			content=input('>')
			if content=='.':
				print('Exit')
				break
			else:
				all.append(content)
		fobj=open(filename,'w')
		str_list=[i+'\n'for i in all]
		fobj.writelines(str_list)
		fobj.close()
		break

2.读入文件并打印出来，如果不存在则提示错误信息

def readFile():
	filename=input('Please enter the file name')
	print(filename)
	try:
		fobj=open(filename,'r')
	except IOError as e:
		print('%s is open error'%filename)
	else:
		for eachLine in fobj:
			print(eachLine)
		fobj.close()