注：所有代码部分均为连续的，“结果”为在jupyter分步运行结果
代码部分：
file = open('hahaha','r+')#先去读一个文件，如果能打开的话就可以写入
结果： （报错，因为当前目录下没有此文件，所以异常）
FileNotFoundError Traceback (most recent call last)
<ipython-input-1-91678176fb53> in <module>()
----> 1 file = open('hahaha','r+')#先去读一个文件，如果能打开的话就可以写入
FileNotFoundError: [Errno 2] No such file or directory: 'hahaha'
#处理异常方式
try:#尝试执行这个语句，如果出现异常则保存在Exception 里面
file = open('hahaha','r+')
except Exception as e:
print(e)
结果：
[Errno 2] No such file or directory: 'hahaha'
try:
file = open('hahaha','r+')
except Exception as e:
print(e)
response = input('Do you want to create it:')
if(response=='yes'):
with open('hahaha','w') as f:
pass
print('The file was created successfully')
else:
pass
结果：
[Errno 2] No such file or directory: 'hahaha'
Do you want to create it:yes
The file was created successfully
try:
file = open('hahaha','r+')
except Exception as e:
print(e)
response = input('Do you want to create it:')
if(response=='yes'):
with open('hahaha','w') as f:
pass
print('The file was created successfully')
else:
pass
else:#没有错误
file.write('hahaha')
file.close()
